BHT-412-SI-91

SUBARU
SERVICE INSTRUCTION FOR UNIVERSAL AUXILIARY
FUEL TANK KIT
EFFECTIVITY
KIT NUMBER NOMENCLATURE MODEL SERIAL NUMBER
1 2 412-706-112-101 Fuel Provisions Kit 412EP 36087 Through 36999
3 4 412-706-112-103 Small Left 16.3 U.S. Gallon Tank Kit 412EP 36087 Through 36999
412EPI 37002 Through 37999
3 4 412-706-112-104 Small Right 16.3 U.S. Gallon Tank Kit 412EP 36087 Through 36999
412EPI 37002 Through 37999
4 412-706-112-105 Large Left 81.7 U.S. Gallon Tank Kit 412EP 36087 Through 36999
412EPI 37002 Through 37999
412EPX 38001 Through 38999
39101 Through 39999
4 412-706-112-106 Large Right 81.7 U.S. Gallon Tank Kit 412EP 36087 Through 36999
412EPI 37002 Through 37999
412EPX 38001 Through 38999
39101 Through 39999
412-706-112-117 Indicator Kit 412EP 36087 Through 36411
1 412-706-112-121 Fuel Provisions Kit 412EPI 37002 Through 37999
1 412-706-112-125 Fuel Provisions Kit 412EPX 38001 Through 38999
39101 Through 39999
4 412-706-112-127 Large Left 81.7 U.S. Gallon Tank Kit 412EPI 37002 Through 37999
412EPX 38001 Through 38999
39101 Through 39999
4 412-706-112-128 Large Right 81.7 U.S. Gallon Tank Kit 412EPI 37002 Through 37999
412EPX 38001 Through 38999
39101 Through 39999

Note: For table notes, refer to page ii.

COPYRIGHT NOTICE
COPYRIGHT 20
BELL ® HELICOPTER TEXTRON INC.
AND BELL HELICOPTER TEXTRON
CANADA LTD.
ALL RIGHTS RESERVED 32672)),&(%2;‡)257:257+7(;$6

9 JANUARY 2012
Export Classification C, ECCN EAR99 REVISION 4 — 21 SEPTEMBER 2020
BHT-412-SI-91

PROPRIETARY RIGHTS NOTICE

These data are proprietary to Bell Textron Inc. Disclosure, reproduction, or use of
these data for any purpose other than helicopter operation or maintenance is
forbidden without prior written authorization from Bell Textron Inc.

DESTINATION CONTROL STATEMENT

WARNING — This document contains technical data whose export is restricted

by the Arms Export Control Act (Title 22, U.S.C., Sec 2751, et. seq.) or the Export
Administration Act of 1979, as amended, Title 50, U.S.C., App. 2401 et. seq.
Violations of these export laws are subject to severe criminal penalties.
Disseminate in accordance with provisions of DoD Directive 5230.25.

PN Rev. 4 21 SEP 2020 Export Classification C, ECCN EAR99

 BHT-412-SI-91

LOG OF REVISIONS

Insert latest revision pages and dispose of superseded ones.

On a revised page, the text and/or illustration affected by the latest revision is shown by a vertical line. A revised
page with only a vertical line next to the page number indicates that text has shifted or that non-technical
correction(s) were made on that page.

Original ........................... 0.......................... 09 JAN 12 Revision.......................... 3...........................15 JUL 20

Revision.......................... 1......................... 03 NOV 16 Revision.......................... 4..........................21 SEP 20
Revision.......................... 2.......................... 10 JAN 20

LOG OF PAGES

Page No. Rev No. Page No. Rev No.

Title .............................................................................4 1-49 – 1-50 ................................................................. 2

PN...............................................................................4 2-1/2-2 ........................................................................ 0
A/B ..............................................................................4 2-3 .............................................................................. 2
i – ii .............................................................................4 2-4 – 2-6 ..................................................................... 0
Help ............................................................................1 2-7 .............................................................................. 2
Customer Feedback ...................................................2 2-8 – 2-14 ................................................................... 0
1-1/1-2 ........................................................................3 2-15 ............................................................................ 2
1-3 – 1-11....................................................................0 2-16 – 2-17 ................................................................. 0
1-12 – 1-13 .................................................................3 2-18 ............................................................................ 1
1-14 – 1-15 .................................................................1 2-19 ............................................................................ 2
1-16 ............................................................................4 2-20 – 2-26 ................................................................. 0
1-17 – 1-18 .................................................................0 2-27/2-28 .................................................................... 2
1-19 ............................................................................1 3-1/3-2 ........................................................................ 3
1-20 – 1-22 .................................................................0 3-3 .............................................................................. 0
1-23 ............................................................................1 3-4 .............................................................................. 4
1-24 – 1-36 .................................................................0 3-5 – 3-16 ................................................................... 0
1-36A – 1-36H ............................................................2 3-17 – 3-18 ................................................................. 1
1-36I/1-36J .................................................................2 3-19 – 3-21 ................................................................. 4
1-37 ............................................................................2 3-22 – 3-26 ................................................................. 3
1-38 ............................................................................3 3-27/3-28 .................................................................... 3
1-39 – 1-48 .................................................................0

LIST OF CHAPTERS

Chapter Description Page

1 Installation Procedures ................................................................................................. 1-1

2 Operation and Maintenance ......................................................................................... 2-1
3 Parts Information and Kit Inventory .............................................................................. 3-1

Export Classification C, ECCN EAR99 21 SEP 2020 Rev. 4 A/B

 BHT-412-SI-91

APPROVAL AND VERIFICATION

The Engineering aspects of this document are FAA approved.

Kit 412-706-112-101 has been verified by first article installation on Model 412EP, S/N 36559, dated 19 September
2011.

Kit 412-706-112-103 has been verified by first article installation on Model 412EP, S/N 36559, dated 19 September
2011.

Kit 412-706-112-104 has been verified by first article installation on Model 412EP, S/N 36559, dated 19 September
2011.

Kit 412-706-112-105 has been verified by first article installation on Model 412EP, S/N 36559, dated 19 September
2011.

Kit 412-706-112-106 has been verified by first article installation on Model 412EP, S/N 36559, dated 19 September
2011.

Kit 412-706-112-117 has been verified by first article installation on Model 412EP, S/N 36559, dated 19 September
2011.

Kit 412-706-112-121 has been verified by similarity to kit 412-706-112-101.

Kit 412-706-112-125 has been verified by similarity to kit 412-706-112-121.

Kit 412-706-112-127 has been verified by similarity to kit 412-706-112-105.

Kit 412-706-112-128 has been verified by similarity to kit 412-706-112-106.

Export Classification C, ECCN EAR99 21 SEP 2020 Rev. 4 i

BHT-412-SI-91

EFFECTIVITY (CONT)
NOTES:

1 Provisions Kit must be installed prior to, or concurrently with kit -103, -104, -105, -106, -127 or
-128.
2 Indicator Kit 412-706-112-117 must be installed on S/N 36087 through 36411 in conjunction with
Provisions Kit -101.
3 Edging 412-706-112-119 color and style to be specified when kit is ordered.
4 Airline Seat Kit 412-706-028 (BHT-412-SI-43) is not compatible when an auxiliary fuel tank is
installed.

ii Rev. 4 21 SEP 2020 Export Classification C, ECCN EAR99

 H ELP

E VALUATE

L OGISTICS

P UBLICATIONS

Have you found something wrong with this manual — an

error, an inconsistency, unclear instructions, etc.? Although
we strive for accuracy and clarity, we may make errors on
occasion. If we do and you discover it, we would appreciate
your telling us about it so that we can change whatever is
incorrect or unclear. Please be as specific as possible.

Your complaint or suggestion will be acknowledged and we

will tell you what we intend to do.

You may use the enclosed Customer Feedback form, as

applicable, to inform us where we have erred.

Your assistance is sincerely appreciated.

Export Classification C, ECCN EAR99

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 BHT-412-SI-91

CHAPTER 1 — INSTALLATION PROCEDURES

TABLE OF CONTENTS

Paragraph Page
Number Title Number

1-1 General Information ............................................................................................ 1-3

1-2 Preparation ......................................................................................................... 1-3
1-3 Standard and Deluxe Interior — Modification ..................................................... 1-6
1-4 Fuel Provision Kit (412-706-112-101, -121 and -125) — Installation.................. 1-12
1-5 Fuel Quantity Indicator Kit (412-706-112-117) — Replacement......................... 1-19
1-6 Small Left Tank Assembly (412-706-112-103) — Installation............................. 1-21
1-7 Small Right Tank Assembly (412-706-112-104) — Installation .......................... 1-25
1-8 Large Left Tank Assembly (412-706-112-105) — Installation ............................ 1-29
1-9 Large Right Tank Assembly (412-706-112-106) — Installation .......................... 1-33
1-9A Large Left Tank Assembly (412-706-112-127) — Installation ............................ 1-36A
1-9B Large Right Tank Assembly (412-706-112-128) — Installation .......................... 1-36F
1-10 Restraint, Guide Assemblies, and Seat Belts — Installation .............................. 1-37
1-11 Tank Seat Cushions and Life Vest Pockets — Installation ................................. 1-38
1-12 Auxiliary Fuel System — Pressure Testing......................................................... 1-38
1-13 Auxiliary Fuel System — Electrical Installation ................................................... 1-41
1-14 Small Tank Assembly — Electrical Installation.............................................. 1-41
1-15 Large Tank Assembly — Electrical Installation.............................................. 1-46
1-16 Restoration.......................................................................................................... 1-50

FIGURES

Figure Page
Number Title Number

1-1 Preparation ......................................................................................................... 1-4

1-2 Standard and Deluxe Interior — Modification ..................................................... 1-8
1-3 Fuel Provision Kit (412-706-112-101, -121 and -125) — Installation.................. 1-13
1-4 Fuel Quantity Indicator Kit (412-706-112-117) — Replacement......................... 1-20
1-5 Small Left Tank Assembly (412-706-112-103) — Installation............................. 1-22
1-6 Small Right Tank Assembly (412-706-112-104) — Installation ......................... 1-26
1-7 Large Left Tank Assembly (412-706-112-105) — Installation ............................ 1-30
1-8 Large Right Tank Assembly (412-706-112-106) — Installation .......................... 1-34
1-8A Large Left Tank Assembly (412-706-112-127) — Installation ............................ 1-36B
1-8B Large Right Tank Assembly (412-706-112-128) — Installation .......................... 1-36H
1-9 Tank Seat Cushions and Restraint Assembly — Installation.............................. 1-39
1-10 Small Tank Assembly — Electrical Installation ................................................... 1-42
1-11 Large Tank Assembly — Electrical Installation................................................... 1-47

Export Classification C, ECCN EAR99 15 JUL 2020 Rev. 3 1-1/1-2

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 BHT-412-SI-91

INSTALLATION PROCEDURES

1-1. GENERAL INFORMATION 9. Following any drilling or cutting, remove burrs

and metal particles. Clean and touch up the surfaces
as necessary (BHT-ALL-SPM).
1. This Service Instruction provides the procedures
to install the Universal Auxiliary Fuel Tank Kit on the
helicopter. 10. For modification or repairs to glass or carbon fiber
reinforced composites, refer to the BHT-ALL-SRM,
Chapter 4.
2. It is the responsibility of the installer to make sure
that newly installed equipment/systems do not 11. Refer to the BHT-ELEC-SPM for the electrical
interfere with, or are susceptible to, the normal installation procedures.
operation of other equipment installed in the
helicopter. Refer to General Information Letter (IL) 12. It is recommended that an experienced electrical/
GEN-07-113 for additional information. avionics person performs all steps pertaining to
connector disassembly/reassembly. If not specified in
3. All openings and ports in components, hoses, these installation procedures, refer to the
and/or tubes disconnected or removed to facilitate the BHT-ELEC-SPM for electrical wiring practices.
modification must be capped, plugged, or otherwise
sealed to prevent contamination during the 13. Perform a continuity check on all wiring newly
modification. installed or disturbed during this modification.

14. Unless otherwise noted, all hose and wire bundle

4. Tag all parts, including attaching hardware clamps should be installed to provide optimum
(unless otherwise noted) removed to gain access to clearance with structure, component, flight controls,
work area. Protect parts from damage until reinstalled. and other hoses and wire bundles.

5. Retain all parts and attaching hardware for 15. Install decals (BHT-ALL-SPM, Chapter 8).
reassembly, unless otherwise noted.
1-2. PREPARATION
6. Prior to installing any previously removed items
1. Defuel helicopter (BHT-412-MM-2, Chapter 12).
(including hardware, hoses, fluid lines/tubes,
components, electrical wiring, etc.), do a visual
inspection for wear, mechanical damage, and 2. Electrically ground the helicopter for safe
corrosion damage. Repair or replace items, as maintenance.
necessary, prior to installation on the helicopter.
3. Disconnect the battery and external power from
the helicopter (BHT-412-MM-10, Chapter 96).
7. Consumable materials may or may not be
supplied with the kit, depending on customer’s 4. If necessary, remove the left and/or right
requirements of consumable items at the time the kit passenger/cargo door (BHT-412-MM-5, Chapter 52).
was ordered. To inform maintenance personnel of
consumables necessary, a MATERIALS REQUIRED
5. Remove the access doors and panels as per the
statement is provided at the beginning of each
instructions in the Miscellaneous Access Doors and
paragraph, as applicable. Refer to the BHT-ALL-SPM
Panels (BHT-412-MM-5, Chapter 52) to access the
for information on consumable materials (C-XXX).
work areas, as shown in Figure 1-1.

8. Draw layout on sheet metal using a fine-tipped 6. If the helicopter is equipped with the Utility
non-corrosive ink marker or equivalent. To prevent Passenger Seat Installation kit (BHT-412-SI-26),
structural damage, do not use metal scribers or lead remove the restraints and fittings from the aft cabin
pencils. area. Retain all parts for later installation.

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BHT-412-SI-91

2
1

6
3

5
4

LOOKING INBOARD - LEFT SIDE

2
1

6
3

5
4

LOOKING INBOARD - RIGHT SIDE

412_SI_91_0001a
Figure 1-1. Preparation (Sheet 1 of 2)

1-4 9 JAN 2012 ECCN EAR99

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 BHT-412-SI-91

FWD

VIEW LOOKING UP

1. Passenger cargo door

2. Pylon access door
3. Pylon access door
4. Auxiliary fuel vent cover (small tank)
5. Auxiliary fuel vent cover (large tank)
6. Pylon access door
7. Access panel

412_SI_91_0001b
Figure 1-1. Preparation (Sheet 2 of 2)

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BHT-412-SI-91

7. If the helicopter is equipped with the Airline Seat (2) At the 3/16-holes location, mark the holes
Kit (BHT-412-SI-43), the restraints and the guides are with a grease pencil on the blanket (5).
already installed. In this case, the restraints and the
guides supplied with this kit may be stored as (3) Remove the edging (6 or 7) from the
necessary. blanket (5).

8. If equipped, remove the deluxe interior blanket (4) Draw a line between each grease pencil
from the pylon island beam and the aft cabin mark.
bulkhead.
(5) Cut the blanket (5).
1-3. STANDARD AND DELUXE INTERIOR
(6) As applicable, apply adhesive (C-324) to
— MODIFICATION the back side of the edging (6 or 7).

(7) Put the edging (6 or 7) in position on the

MATERIALS REQUIRED blanket (5) and fold back the tabs.

Refer to BHT-ALL-SPM for specifications. b. Locate the edgings (9 or 10), as necessary, on

the blanket (4) as follows:
NUMBER NOMENCLATURE

C-324 Adhesive (1) Put the edging (9 or 10) in position on the

blanket (4), as shown in Detail I or J.

(2) At 3/16-holes location, mark the holes

NOTE
with a grease pencil on the blanket (4).
The following procedure is for the standard
interior blankets on the left side. The (3) Remove the edging (9 or 10) from the
procedure is the same for the standard blanket (4).
interior blankets on the right side, except
where indicated. (4) Draw a line between each grease pencil
mark.
NOTE
(5) Cut the blanket (4).
The modified standard or deluxe interior
blankets may remain installed when
(6) As necessary, apply adhesive (C-324) to
auxiliary fuel tanks are not installed on the
the back side of the edging (9 or 10).
helicopter.
(7) Put the edging (9 or 10) in position on the
NOTE blanket (4) and fold back the tabs.
If the edgings (6, 7, 8, 9, and 10) are not
c. Remove the blankets (4 and 5) from the aft
bonded to the blankets (4 and 5), modify
cabin bulkhead and the pylon island beam.
and install all of them at the same time.

d. Locate the edgings (8) on the blanket (5) as

1. To modify the standard interior blankets (4 and 5,
follows:
Figure 1-2), do as follows:
(1) Partially, remove the blanket (5) from the
a. Locate the edgings (6 or 7), as necessary, on pylon island beam.
the blanket (5) as follows:
(2) Mark the head of the screws of the
(1) Put the edging (6 or 7) in position on the auxiliary fuel vent cover (4 or 5, Figure 1-1), as
blanket (5), as shown in Detail L. necessary, with a grease pencil.

1-6 9 JAN 2012 ECCN EAR99

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 BHT-412-SI-91

(3) Put the blanket (5, Figure 1-2) back in 412-070-606, respectively. For the large
position on the pylon island beam and apply firm tank assembly, replace the pylon island
pressure by hand at the screw locations. blanket 412-070-524 with 412-070-833 and
the aft cabin bulkhead blanket 412-070-553
(4) On the back of the blanket (5) locate the with 412-070-834, respectively.
grease pencil mark from the head of the screws.
b. For the small left tank assembly, cut the
blankets (1 and 2) along the seam, as shown in
(5) Draw a line between each grease pencil
Detail A.
mark.

(6) Cut the blanket (5). NOTE

If you remove the small tank, you will have
(7) As necessary, apply adhesive (C-324) to to install the pieces of the blankets (1
the back side of the edging (8). and 2) back in position.

(8) Put the edgings (8) in position and make c. Retain the removed pieces of the blankets (1
sure to center the 3/16-holes between the screws. and 2).

(9) Fold back the tabs of the edgings (8) on d. Repeat step b and step c for the small right
the blanket (5). tank assembly.

e. Sew the edgings (6 or 7, 8, 9 or 10), as e. For the large left tank assembly, cut the
applicable, on the blankets (4 and 5) per blankets (1 and 2) along the seam, as shown in
FED-STD-751. Detail B.

NOTE NOTE
The following procedure is for the deluxe If you remove the large tank assembly, you
interior blankets on the left side. The will have to install the pieces of the deluxe
procedure is the same for the deluxe blanket (1 and 2) back in position.
interior blankets on the right side.
f. Retain the removed pieces of the blankets (1
2. To modify the deluxe blankets (1 and 2), do as and 2).
follows:
g. Repeat step e and step f for the large right
a. Remove the blankets (1 and 2) from the aft tank assembly.
cabin bulkhead and the pylon island beam.
h. Modify the deluxe blanket (1) as follows:

NOTE
(1) Cut the blanket (1) to the dimension
As an alternate method to cut the existing shown in View E.
deluxe blankets, the deluxe blankets can be
ordered through Bell Helicopter Textron
facilities. For the small tank assembly, (2) Fold back the piece of blanket (1) as
replace the pylon island blanket shown in Section F-F.
412-070-524 with 412-070-607 and the aft
cabin bulkhead blanket 412-070-553 with (3) Sew the blanket (1) per FED-STD-751.

ECCN EAR99 9 JAN 2012 1-7

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BHT-412-SI-91

SEE DETAILS A, B, G AND H

PYLON
AFT CABIN AFT CABIN ISLAND
BULKHEAD BULKHEAD BEAM
AFT AFT
PYLON
ISLAND 1
BEAM SEAM
1
1 2

SEAM 1 2

WL
WL WL
E 33.15 WL
35.67 33.15
C 35.67

BL
31.05

1 3
STA CABIN
CABIN STA
132.70 FLOOR
SEAM 3 131.56
FLOOR

DETAIL A DETAIL B
DELUXE INTERIOR SMALL TANK DELUXE INTERIOR LARGE TANK
RIGHT SIDE SHOWN RIGHT SIDE SHOWN
(LEFT SIDE OPPOSITE) (LEFT SIDE OPPOSITE)

412_SI_91_0010a
Figure 1-2. Standard and Deluxe Interior — Modification (Sheet 1 of 4)

1-8 9 JAN 2012 ECCN EAR99

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 BHT-412-SI-91

BL BL
14.00 31.05 11 2

17.05 IN.
(433.0 mm)

STA
BL
166.00
31.05
11 2

5
D D 14 3

A THREAD
13
12
14 3
SECTION D-D
STA
132.55
STA
129.00

VIEW C
BL
31.05
THREAD

WL
35.67
3.90 IN.
(99.0 mm) THREAD

1.00 IN. 1 4 SECTION F-F

F
(25.4 mm)

1.90 IN.
(48.3 mm)
VIEW E

412_SI_91_0010b
Figure 1-2. Standard and Deluxe Interior — Modification (Sheet 2 of 4)

ECCN EAR99 9 JAN 2012 1-9

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BHT-412-SI-91

PYLON
AFT CABIN AFT CABIN ISLAND
BULKHEAD BULKHEAD BEAM
AFT AFT
PYLON
ISLAND
BEAM
5
5
4 8
7 4 7
6 6

9
SEE DETAIL K
WL
WL WL
8 33.15 WL
35.67 33.15
35.67

10
SEE DETAIL L
SEE DETAIL L
SEE DETAIL J

BL
31.05 BL
SEE DETAIL I CABIN
CABIN FLOOR
FLOOR 31.05
DETAIL G DETAIL H
STANDARD INTERIOR SMALL TANK STANDARD INTERIOR LARGE TANK
RIGHT SIDE SHOWN RIGHT SIDE SHOWN
(LEFT SIDE OPPOSITE) (LEFT SIDE OPPOSITE)

4
2.1 IN. THREAD
(53.3 mm)
0.7 IN.
1.00 IN. (17.8 mm)
(25.4 mm)

1.00 IN.
(25.4 mm) EXISTING WL
CUTOUT 35.67
IN BLANKET
WL
35.67
1.00 IN.
(25.4 mm)
THREAD
.50 IN.
(12.70 mm)
4
CUTOUT
3 A 9 CUTOUT IN BLANKET 10 A 3
IN BLANKET ONLY BL
31.05
DETAIL I
DETAIL J
412_SI_91_0010c
Figure 1-2. Standard and Deluxe Interior — Modification (Sheet 3 of 4)

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 BHT-412-SI-91

8 A 3
CUTOUT
5
0.6 IN.
(15.2 mm)
1.84 IN.
CUTOUT
(46.7 mm)
DIAMETER WLWL
34.25
3.5 IN. 34.25
THREAD (88.9 mm)

STA
THREAD 144.00
WL
30.91 3.1 IN.
(78.7 mm) THREAD

CUTOUT 6 A 3 STA
DIAMETER WL 7 136.80
3.5 IN. 51.10
(88.9 mm) DETAIL L

8 A 3

DETAIL K
1. Blanket (Ref) 8. Edging (412-706-112-109) 4 Reqd
2. Blanket (Ref) 9. Edging (412-706-112-111) 2 Reqd
3. Carpet (Ref) 10. Edging (205-706-044-005) 2 Reqd
4. Blanket (Ref) 11. Edging (412-706-112-119) 2 Reqd
5. Blanket (Ref) 12. Hook (50-029-7BP55P)
6. Left side edging (412-706-112-107) 2 Reqd 13. Pile (50-029-12BP55P)
7. Right side edging (412-706-112-108) 2 Reqd 14. Carpet (Ref)

A ADHESIVE (C-324)

NOTES
1 Retain the blankets (1 and 2) and carpet (14) cut outs for later installation when tank is removed.

2 Color of edging (11), material and style to be specified when kit is ordered and to be flame
resistant per 299-947-160 CL III.

3 It is permitted to glue the edgings (6, 7, 8, 9, and 10) to blankets (4 and 5) with adhesive (C-324) prior
to sewing per FED-STD-751, to ease installation.

4 Remove material from this area and seam edges with thread per FED-STD-751.

5 Bezels were located at this location.

412_SI_91_0010d
Figure 1-2. Standard and Deluxe Interior — Modification (Sheet 4 of 4)

ECCN EAR99 9 JAN 2012 1-11

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BHT-412-SI-91

1-4. FUEL PROVISION KIT

NOTE
(412-706-112-101, -121 AND -125) —
The following procedure is for the deluxe INSTALLATION
interior carpet on the left side. The
procedure is the same for the deluxe MATERIALS REQUIRED
interior carpet on the right side.
Refer to BHT-ALL-SPM for specifications.
3. To modify the deluxe interior carpet (3), do as
follows: NUMBER NOMENCLATURE

C-024 Assembly fluid

a. For the small left tank assembly and if the
existing carpet (3) is already modified, cut the carpet C-285 Isopropyl Alcohol
along the seam, as shown in Detail A. Retain the
removed piece for later installation. C-328 Sealant

b. For the small left tank assembly and if the C-349 Edge Sealer
carpets (3) 412-070-529-125/-126 are not modified, do
as follows: C-486 Cheesecloth

(1) Cut the carpet (3) to the dimension

shown in View C.
WARNING
(2) Remove and discard the bezels from the
carpet (3).
ONLY APPROVED, EXPLOSION PROOF
TYPE LIGHTS ARE TO BE USED NEAR
(3) Put the edging (11) and the pile (13) in
OPEN FUEL CELLS AND FUEL LINES.
position on the carpet (3), as shown in Section D-D.

(4) Sew the edging (11) and the pile (13) on

the carpet (3) per FED-STD-751. WARNING

(5) Put the edging (11) in position on the

carpet (14), as shown in Section D-D. OBEY ALL THE SAFETY PRECAUTIONS
WHEN YOU DO MAINTENANCE ON
(6) Sew the edging (11) on the carpet (14) FUEL SYSTEM EQUIPMENT.
per FED-STD-751.
NOTE
(7) Apply adhesive (C-324) to the carpet (14)
and install the hook (12) on the carpet, as shown in It is recommended that you do not tighten
Section D-D. the coupling nut on the tube assembly until
the necessary routing and orientation of the
tube assembly is achieved, to prevent
NOTE interference, chafing, or preloading.

If you remove the small tank, you will have

to install the pieces of carpet (3 or 14) back NOTE
in position.
The following procedure is for the
installation of the fuel provision on the left
(8) Retain the carpet (14) cutout. side. The procedure is the same for the
right side, except where indicated
(9) Install the carpet (3) on the cabin floor.
1. Remove the screws (72, 73, and 74, Figure 1-3)
c. For the large tank assemblies, remove the and the panel assemblies (71 and 75) from the cabin
carpet (3). floor.

1-12 Rev. 3 15 JUL 2020 Export Classification C, ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

I H A

8
10
7

22
EXISTING
21 C BRACKET
20
15 19 9
BL
14 17 18
64 2.50
13 DETAIL B
BL
12 16 5.90
11 25
1 23
10
26 1
24
SEE DETAIL B 65
5 27

WL BL
48.40 31.05
1 2

3 1

BL BL BL
14.00 0.00 14.00

VIEW A SEE DETAIL E

LOOKING AFT BL
24.50

NO OBJECT BEYOND THIS POINT 412_SI_91_0002a_c01

Figure 1-3. Fuel Provision Kit (412-706-112-101, -121 and -125) — Installation (Sheet 1 of 4)

Export Classification C, ECCN EAR99 15 JUL 2020 Rev. 3 1-13

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

4 17

10
65
29
30
25
31
68 32
F 1
69 33
70
27 34
76
25
5
3

28

CYCLIC SUPPORT ASSEMBLY

BL BL BL
14.00 0.00 14.00

VIEW C
LOOKING DOWN 67
62 BL
49 66
18.26
BL CABIN
48 51 60
14.00 FLOOR
47 63
WL
46
BL 22.00
18.26 45 58 61
71
57
50 75
56
84 51

59 DETAIL E
FS 84
(LEFT SIDE SHOWN
158.44 50 1.00 IN. RIGHT SIDE OPPOSITE)
44 43 42 41 40 (25.4 mm)
55 54 53 52 2

VIEW D 35 36 37 38
LOOKING DOWN
(LEFT SIDE SHOWN
RIGHT SIDE OPPOSITE)
39
0.56 IN. HOLE 0.196 TO 0.201 IN.
(12.2 mm) (4.99 TO 5.10 mm)
4

VIEW F
412_SI_91_0002b

Figure 1-3. Fuel Provision Kit (412-706-112-101 and -121) — Installation (Sheet 2 of 4)

1-14 Rev. 1 3 NOV 2016 Export Classification C, ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

60
71 72 73 74 75 S1

CABIN FLOOR

77 VIEW G
LEFT SIDE SHOWN
(RIGHT SIDE OPPOSITE)

78

79
80

81 82

85

S 2 81

83
VIEW H VIEW I
LOOKING FORWARD LOOKING INBOARD RIGHT SIDE
(KIT-101) (KIT-121)
412_SI_91_0002c_c01
Figure 1-3. Fuel Provision Kit (412-706-112-101 and -121) — Installation (Sheet 3 of 4)

Export Classification C, ECCN EAR99 3 NOV 2016 Rev. 1 1-15

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

1. Tee (Ref) 43. Washer (NAS1149D0332J) 4 Reqd

2. Cap (Ref) 44. Nut (NAS9926-3L) 4 Reqd
3. Plug (AS5168W08) 45. Screw (MS27039-1-09) 2 Reqd
4. Tube assembly (212-060-666-001) 46. Clamp (MS21919WDG22) 2 Reqd
5. Plug (AS5168W08) 47. Clamp (MS21919WDG18) 2 Reqd
6. Screw (MS27039-1-08) 48. Washer (NAS1149D0332J) 2 Reqd
7. Clamp (MS21919WDG8) 49. Nut (NAS9926-3L) 2 Reqd
8. Washer (NAS1149D0316J) 50. Hose assembly (144020-2) 2 Reqd
9. Nut (NAS9926-3L) 51. Hose assembly (Ref)
10. Tube assembly (212-060-668-001) 52. Bolt (Ref)
11. Screw (MS27039-1-08) 53. Washer (Ref)
12. Clamp (MS21919WDG10) 54. Cover plate (Ref)
13. Clamp (MS21919WDG8) 55. Packing (Ref)
14. Washer (NAS1149D0316J) 56. Packing (MS29513-220) 2 Reqd
15. Nut (NAS9926-3L) 57. Bolt (NAS6604-4) 8 Reqd
16. Union (AS5174W0808) 58. Washer (NAS1149D0416J) 8 Reqd
17. Tube assembly (212-060-667-001) 59. Fitting (Ref)
18. Screw (MS27039-1-08) 60. Cover assembly (Ref)
19. Washer (NAS1149D0316J) 2 Reqd 61. Stowage plug (144020-3) 2 Reqd
20. Clamp (MS21919WDG10) 62. Screw (MS27039-1-09) 2 Reqd
21. Clamp (MS21919WDG8) 63. Washer (NAS1149D0332J) 2 Reqd
22. Nut (NAS9926-3L) 64. Tube assembly (Ref)
23. Cap (Ref) 65. Elbow (Ref)
24. Tee (Ref) 66. Washer (Ref)
25. Tube assembly (412-060-656-101) 67. Screw (Ref)
26. Cap (Ref) 68. Fitting (Ref)
27. Plug (AS5168W08) 69. Cap (Ref)
28. Nut (Ref) 70. Washer (Ref)
29. Bracket (20-032-3D) 71. Left panel assembly (Ref)
30. Screw (MS27039-1-15) 72. Screw (Ref)
31. Spacer (NAS43DD3-32N) 73. Screw (Ref)
32. Clamp (MS21919WDG8) 74. Screw (Ref)
33. Washer (NAS1149D0332J) 75. Right panel assembly (Ref)
34. Nut (NAS9926-3L) 76. Bolt (Ref)
35. Screw (MS27039-1-08) 77. Pin (Ref)
36. Washer (NAS1149D0332J) 78. Ring (Ref)
37. Clamp (MS21919WDG8) 79. Cotter pin (Ref)
38. Nut (NAS9926-3L) 80. Pin (Ref)
39. Oil filter bracket (Ref) 81. 10-cell fuel system decal (412-706-112-113)
40. Screw (MS27039-1-09) 4 Reqd 82. Nine-cell fuel system decal (412-706-112-115)
41. Clamp (MS21919WDG22) 4 Reqd 83. Instrument panel (Ref)
42. Clamp (MS21919WDG18) 4 Reqd 84. Hose assembly (Ref)
85. Panel assembly

ASSEMBLY FLUID (C-024)

SEALANT (C-328)
1
EDGE SEALER (C-349)
2

NOTES
1 Remove the cap installed at this location.

2 Remove and retain the existing hardware.

NO OBJECT BEYOND THIS POINT 412_SI_91_0002d_c02

Figure 1-3. Fuel Provision Kit (412-706-112-101 and -121) — Installation (Sheet 4 of 4)

1-16 Rev. 4 21 SEP 2020 Export Classification C, ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

2. In the cabin floor area, install the hose assembly

NOTE
(50, View D) as follows:
Do step l through step t to help position the
hose assemblies (50, 51, and 84) in the
NOTE cabin floor area.

When the two buttons are extended on the l. Temporarily put the panel assemblies (71
self-sealing disconnect of the hose and 75) in position on the cabin floor.
assembly (50), it indicates that the
self-sealing disconnect is locked. m. Put the cover assembly (60) in position over
the stowage plug (61).
a. Press on the two buttons of the self-sealing
disconnect and connect the hose assembly (50) to the n. Install the screw (62) and the washer (63) to
stowage plug (61, Detail E). Make sure the self-sealing secure the stowage plug (61) to the cover assembly
disconnect is locked. (60). Tighten the screw (62).

o. Install the cover assembly (60) with the

b. Remove the bolts (52), washers (53), cover screws (67) and the washers (66). Tighten the screws
plate (54), and packing (55) from the fitting (59). (67).
Retain the hardware and discard the packing (55).
p. Temporarily secure the panel assemblies (71
c. Lubricate a new packing (56) with assembly and 75) of the cabin floor with two screws (72). Tighten
fluid (C-024). the screws (72).

q. Tighten the bolts (58) on the fitting (59).

d. Install the packing (56) in the groove of the
fitting (59). r. Remove the screw (62) and the washer (63)
from the cover assembly (60).
e. Put the hose assembly (50) in position in the
cabin floor area, as shown in Figure 1-3. s. Remove the screws (67), washers (66), and
cover assembly (60) from the panel assemblies (71
and 75).
f. Install the hose assembly (50) on the fitting
(59) with the bolts (57) and the washers (58). Do not
t. Remove the screws (72) and the panel
tighten the bolts (57) at this time. assemblies (71 and 75) from the cabin floor.

g. Put the clamps (46 and 47) in position on the u. To make sure there is no twisting,
hose assemblies (50 and 51). interference, chafing, or preloading, examine the
position of the hose assemblies (50, 51, and 84) and
the positioning of all the previously installed clamps
h. Install the clamps (46 and 47) with the screw and associated fasteners.
(45), washer (48), and nut (49), as shown in View D.
Do not tighten the nut (49) at this time. v. Tighten the nuts (44 and 49).

i. At two locations, put the clamps (41 and 42) in w. Apply sealant (C-328) to the faying surfaces of
position on the hose assemblies (50 and 84). the panel assemblies (71 and 75) and the cabin floor.

x. Install the panel assemblies (71 and 75) of the

j. At two locations, install the clamps (41 and 42)
cabin floor with the screws (72, 73, and 74). Tighten
with the screw (40), washer (43), and nut (44). Do not
the screws (72, 73, and 74).
tighten the nut (44) at this time.
y. Put the cover assembly (60) in position on the
k. Repeat step a through step j for the right side. panel assemblies (71 and 75).

ECCN EAR99 9 JAN 2012 1-17

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

z. Install the screws (62) and the washer (63) to g. Put the clamp (7) in position on the tube
secure the stowage plug (61) to the cover assembly assembly (10).
(60). Tighten the screws (62).
h. Install the clamp (7) on the existing bracket
aa.Install the cover assembly (60) with the with the screw (6), washer (8), and nut (9), as shown
screws (67) and the washers (66). Tighten the screws. in Detail B.

i. To make sure there is no twisting,

NOTE interference, chafing, or preloading, examine the
To ease the installation, step 3 through position of the tube assemblies (10 and 17) and the
step 6 should not be done on the helicopter. positioning of all the previously installed clamps and
associated fasteners.
3. Install the plug (5) on the tube assembly (10).
Tighten the plug (5). j. Tighten the coupling nuts of the tube
assemblies (10 and 17) at the union (16) and the
tee (24).
4. Install the union (16) on the tube assembly (17).

k. Tighten the nuts (9, 15, and 22) that are part of
5. Install the plug (27) on the tube assembly (25). the clamping installation.
Tighten the plug (27).
l. Connect the tube assembly (25) to the elbow
6. Install the plug (3) on the tube assembly (4). (65). Do not tighten the coupling nut at this time.
Tighten the plug (3).
m. Remove the nut (28, View C), washer (70),
7. In the pylon area, remove the caps (2, 23, and and bolt (76) from the cyclic support assembly.
26) from the tees (1 and 24) and elbow (65). Retain
the caps (2, 23, and 26). n. Put the bracket (29) in position between the
cyclic support assembly and the existing bracket, as
shown in View C.
8. In the pylon island area, install the tube
assemblies (4, 10, 17, and 25) as follows:
o. Install the bolt (76), washer (70), and nut (28)
on the cyclic support assembly. Do not tighten the nut
a. Connect the tube assembly (17) to the tee at this time.
(24). Do not tighten the coupling nut at this time.
p. Put the clamp (32) in position on the tube
b. Put the clamps (20 and 21) in position on the assembly (25).
tube assemblies (17 and 64).
q. Install the clamp (32) with the screw (30),
c. Install the clamps (20 and 21) with the screw spacer (31), washer (33), and nut (34). Do not tighten
(18), washers (19), and nut (22). Do not tighten the nut the nut (34) at this time.
(22) at this time.
r. To make sure there is no twisting,
d. Connect the tube assembly (10) to the union interference, chafing, or preloading, examine the
(16). Do not tighten the coupling nut at this time. position of the tube assembly (25) and the positioning
of all the previously installed clamp and associated
e. Put the clamps (12 and 13) in position on the fasteners.
tube assemblies (17 and 64).
s. Tighten the coupling nut of the tube
f. Install the clamps (12 and 13) with the screw assembly (25).
(11), washers (14), and nut (15). Do not tighten the nut
(15) at this time. t. Tighten the nuts (28 and 34).

1-18 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

10. For kit 412-706-112-101, if the helicopter is

equipped with a 10-cell fuel system, install the decal
CAUTION
(81) on the instrument panel (83) as follows:

USE A STOP DRILL OR DAMAGE TO a. Remove the existing decal from the
T H E O I L F I LT E R A S S E M B LY C A N instrument panel (83).
OCCUR.
b. Clean the instrument panel surface with a
u. On the lower right side, locate and drill one cheesecloth (C-486) moistened with isopropyl alcohol
hole 0.196 to 0.201 inch (4.99 to 5.10 mm) in diameter (C-285).
through the oil filter bracket (39) with a No. 9 drill, as
shown in View F.
c. Install the 10-cell fuel system decal (81) on the
instrument panel (83), as shown in View H. Apply edge
v. Connect the tube assembly (4) to the tee (1). sealer (C-349) to the edges of the decal.
Do not tighten the coupling nut at this time.
11. For kit 412-706-112-121, install the decal (81) on
w. Put the clamp (37) in position on the tube the panel assembly (85) as follows:
assembly (4).
a. Remove the existing decal from the panel
x. Install the clamp (37) on the oil filter bracket assembly (85).
(39) with the screw (35), washers (36), and nut (38).
Do not tighten the nut (38) at this time. b. Clean the panel assembly surface with a
cheesecloth (C-486) moistened with isopropyl alcohol
y. To make sure there is no twisting, (C-285).
interference, chafing, or preloading, examine the
position of the tube assembly (4) and the positioning of c. Install the 10-cell fuel system decal (81) on the
all the previously installed clamps and associated panel assembly (85), as shown in View I. Apply edge
fasteners. sealer (C-349) to the edges of the decal.

z. Tighten the coupling nut of the tube 12. Do a pressure test of the fuel system installation
assembly (4). as per paragraph 1-12.

aa.Tighten the nut (38). 1-5. FUEL QUANTITY INDICATOR KIT

(412-706-112-117) — REPLACEMENT
9. For kit 412-706-112-101, if the helicopter is
equipped with a Nine-cell Fuel System Kit
(BHT-412-SI-77), install the decal (82) on the NOTE
instrument panel (83) as follows: The following procedure is for helicopters
S/N 36087 through 36411 only.
a. Remove the existing decal from the
instrument panel (83). 1. Replace the fuel quantity indicator as follows:

b. Clean the instrument panel surface with a a. Remove the screw (3, Figure 1-4) and the
cheesecloth (C-486) moistened with isopropyl alcohol existing fuel quantity indicator from the instrument
(C-285). panel (2). Retain the screw (3).

c. Install the nine-cell fuel system decal (82) on b. Install the fuel quantity indicator (1) on the
the instrument panel (83), as shown in View H. Apply instrument panel (2) with the screw (3). Tighten the
edge sealer (C-349) to the edges of the decal. screw (3).

Export Classification C, ECCN EAR99 3 NOV 2016 Rev. 1 1-19

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

VIEW A

1. Fuel quantity indicator (214-175-257-109)

2. Instrument panel (Ref)
3. Screw (Ref)

412_SI_91_0011
Figure 1-4. Fuel Quantity Indicator Kit (412-706-112-117) — Replacement

1-20 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

1-6. SMALL LEFT TANK ASSEMBLY 6. Install the washers (5, Figure 1-9) and the rings
(412-706-112-103) — INSTALLATION (6) on the pylon island beam. Tighten the rings (6).

7. Remove and discard the existing plug from the

WARNING fuselage skin and install the grommet (29, Figure 1-5).

8. If the helicopter is equipped with the Utility

ONLY APPROVED, EXPLOSION PROOF Passenger Seat Installation kit (BHT-412-SI-26), do as
TYPE LIGHTS ARE TO BE USED NEAR follows:
OPEN FUEL CELLS AND FUEL LINES.
a. Remove the cotter pin (79, Figure 1-3), pin
(77), and ring (78) from the pin (80) on the cabin floor.
WARNING Retain the ring (78). Discard the cotter pin (79).

b. Install the pin (77) on the pin (80) and secure

OBEY ALL THE SAFETY PRECAUTIONS with a new cotter pin (79) on the cabin floor, as shown
WHEN YOU DO MAINTENANCE ON in View G.
FUEL SYSTEM EQUIPMENT.
NOTE
NOTE
Two persons are necessary to install the
The following procedure makes reference small left tank assembly.
to a small tank assembly. For clarification,
the small tank assembly has a capacity of 9. Install the small left tank assembly (1, Figure 1-5)
16.3 U.S. gallons (61.7 L). as follows:

NOTE
It is recommended that you do not tighten CAUTION
the coupling nut on the hose assembly until
the necessary routing and orientation of the
hose assembly is achieved, to prevent BE CAREFUL WHEN HANDLING THE
twisting, interference, chafing, or TANK ASSEMBLY. DAMAGE TO THE
preloading. DRAIN TUBE CAN OCCUR.

1. Remove the access panel (7, Figure 1-1).

Retain all the parts.
CAUTION
2. Remove the auxiliary fuel vent cover (4) from the
pylon island beam. Retain the cover (4) and the BE CAREFUL WHEN POSITIONING THE
hardware. TA N K A S S E M B LY O N T H E C A B I N
FLOOR OR DAMAGE TO THE AFT CABIN
3. Access the hose assembly (14, Figure 1-5), BULKHEAD AND PYLON ISLAND BEAM
press on the two buttons, at the same time pull down, CAN OCCUR.
unlock and disconnect the hose assembly from the
stowage plug (4). a. Install the seal (23) on the frangible valve (24),
as shown in View A.
4. Remove the screws (10), washers (11), and cover
assembly (12) from the cabin floor. Retain the cover b. Put the small left tank assembly (1) in position
assembly (12) and the hardware. on the cabin floor.

5. Install the drain tube (28) on the fitting (26) with c. Route the drain tube (28) through the cabin
the clamp (27). Tighten the clamp (27). floor and the grommet (29).

ECCN EAR99 9 JAN 2012 1-21

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

BL
0.0 FS
166.00

A
SEE DETAIL D

FWD
21

22 25
B
C
1
24
23
FS
132.15

VIEW A
LEFT SIDE
LOOKING DOWN

CABIN AFT
PYLON BULKHEAD
1 3
ISLAND BEAM
T 2
D
FW
5
6
20
7
19
19 9 8

18
17

STA
166.00
16
10 11

T 15 12
(2 PLACES) BL
14.00 WL 13
22.00 BL 4
FLOOR 31.05 14
CABIN FLOOR

VIEW B
LOOKING INBOARD LEFT SIDE
412_SI_91_0003a
Figure 1-5. Small Left Tank Assembly (412-706-112-103) — Installation (Sheet 1 of 2)

1-22 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

BL
31.05

22

WL
22.00
FLOOR 26
BL
14.00
27
14 BL
18.25
FUSELAGE
28 SKIN
1. Small left tank assembly (412-706-112-103) 29
0.750 IN.
2. Bolt (AN5-4A) BL
(19.0 mm)
3. Washer (NAS1149D0563J) 24.50
4. Stowage plug (Ref)
5. Aft fitting (205-062-611-101)
VIEW C
6. Washer (NAS1149D0416J)
LOOKING AFT
7. Bolt (AN4-10A)
8. Bolt (NAS624-6) 2 Reqd
9. Washer (NAS1149D0432J) 2 Reqd
10. Screw (Ref)
11. Washer (Ref)
12. Cover assembly (Ref)
13. Nipple assembly (Ref) 30 21
14. Hose assembly (Ref)
15. Bolt (AN4-5A) 2 Reqd
16. Washer (NAS1149D0463J) 2 Reqd
17. Bolt (AN4-7A)
18. Washer (NAS1149D0463J)
19. Shim (205-030-424-001) 2 Reqd
20. Forward fitting (205-061-698-101)
21. Tee (Ref)
22. Hose assembly (70-061H000V080A)
23. Seal (214-066-063-003)
DETAIL D
24. Frangible valve (Ref)
25. Cap (Ref)
26. Fitting (Ref)
27. Clamp (33-116-3)
28. Drain tube (130-038-17-34)
29. Grommet (MS35489-149)
30. Cap (Ref)

25 TO 35 IN-LBS
T (2.8 TO 4.0 Nm)
412_SI_ 91_0003b_c01

Figure 1-5. Small Left Tank Assembly (412-706-112-103) — Installation (Sheet 2 of 2)

Export Classification C, ECCN EAR99 3 NOV 2016 Rev. 1 1-23

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

laminated shim. Each lamination is

NOTE
0.003 inch (0.08 mm) thick.
When the two buttons are extended on the
self-sealing disconnect of the hose n. If necessary, shim the forward fitting (20) as
assembly (14), it indicates that the follows:
self-sealing disconnect is locked.
(1) As necessary, peel the laminated shim
d. Press on the two buttons of the self-sealing (19) to fill the gap between the small left tank
disconnect and connect the hose assembly (14) to the assembly (1) and the forward fitting (20).
nipple assembly (13). Make sure the self-sealing
disconnect is locked. (2) As necessary, peel the laminated shims
(19) to fill the gap between the pylon island beam and
the forward fitting (20).
e. Install the aft fitting (5) on the small left tank
assembly (1) with the bolts (7 and 8) and the washers (3) Remove the bolts (15 and 17), washers
(6 and 9). Do not tighten the bolts (7 and 8) at this (16 and 18), and forward fitting (20) from the small left
time. tank assembly (1).

f. Temporarily install the aft fitting (5) on the (4) Install the forward fitting (20) and the
cabin aft bulkhead with the bolt (2) and the washer (3). shim (19), as necessary, on the small left tank
Do not tighten the bolt (2) at this time. assembly (1) with the bolt (17) and the washer (18).
Tighten the bolt (17).
g. Temporarily install the forward fitting (20) on
the small left tank assembly (1) with the bolt (17) and (5) Install the forward fitting (20) and the
the washer (18). Do not tighten the bolt (17) at this shims (19), as necessary, on the pylon island beam
with the bolts (15) and the washers (16). Torque the
time.
bolts (15) T .

h. Temporarily install the forward fitting (20) on 10. Remove the cap (30) from the tee (21). Retain
the pylon island beam with the bolts (15) and the the cap (30).
washers (16). Do not tighten the bolts (15) at this time.
11. Connect the straight end of the hose assembly
i. Make sure there is no interference between (22) to the tee (21).
the small left tank assembly (1) and the rings (6,
Figure 1-9). 12. Remove the cap (25) from the frangible valve
(24). Retain the cap (25).
j. If interference exist, move the small left tank
assembly (1) to remove the interference. 13. Connect the hose assembly (22) to the frangible
valve (24).
k. If there is no interference, tighten the bolts (7,
8, and 17, Figure 1-5) and torque the bolts (2 14. To make sure there is no twisting, interference,
and 15) T . chafing, or preloading, examine the position of the
hose assembly (22).
l. Measure the gap between the forward fitting
(20) and the pylon island beam. 15. Tighten the coupling nuts of the hose
assembly (22).
m. Measure the gap between the small left tank
assembly (1) and the forward fitting (20). 16. Install the drain tube (28) 0.75 inch (19.1 mm)
under the fuselage skin, as shown in View C. Make
sure the drain tube (28) is not twisted.
NOTE
The laminated shims (19) are 0.180 inch 17. Cut the end of the drain tube (28) at 45° and
(4.57 mm) of total thickness, and include a make sure the bevel points aft.
solid shim of 0.063 inch (1.60 mm) thick,
and a peelable 0.120-inch (3.05-mm) 18. Install the access panel (7, Figure 1-1).

1-24 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

19. Do a pressure test of the fuel system installation 5. Install the drain tube (29) on the fitting (27) with
as per paragraph 1-12. the clamp (28), as shown in View C. Tighten the clamp
(28).
1-7. SMALL RIGHT TANK ASSEMBLY
(412-706-112-104) — INSTALLATION 6. Install the washers (5, Figure 1-9) and the rings
(6). Tighten the rings.

WARNING 7. Remove and discard the existing plug from the

fuselage skin and install the grommet (30, Figure 1-6).

ONLY APPROVED, EXPLOSION PROOF

8. If the helicopter is equipped with the Utility
TYPE LIGHTS ARE TO BE USED NEAR
Passenger Seat Installation kit (BHT-412-SI-26), do as
OPEN FUEL CELLS AND FUEL LINES.
follows:

WARNING a. Remove the cotter pin (79, Figure 1-3), pin

(77), and ring (78) from pin (80) on the cabin floor.
Retain the ring (78). Discard the cotter pin (79).
OBEY ALL THE SAFETY PRECAUTIONS
WHEN YOU DO MAINTENANCE ON b. Install the pin (77) on the pin (80) and secure
FUEL SYSTEM EQUIPMENT. with a new cotter pin (79) on the cabin floor, as shown
in View G.
NOTE
The following procedure makes reference NOTE
to a small tank assembly. For clarification, Two persons are necessary to install the
the small tank assembly has a capacity of small right tank assembly.
16.3 U.S. gallons (61.7 L).
9. Install the small right tank assembly (1,
NOTE Figure 1-6) as follows:
It is recommended that you do not tighten
the coupling nut on the hose assembly until
the necessary routing and orientation of the
hose assembly is achieved, to prevent CAUTION
twisting, interference, chafing, or
preloading.
BE CAREFUL WHEN HANDLING THE
1. Remove the access panel (7, Figure 1-1). TANK ASSEMBLY. DAMAGE TO THE
Retain all the parts. DRAIN TUBE CAN OCCUR.

2. Remove the auxiliary fuel vent cover (4) from the

pylon island beam. Retain the cover (4) and the CAUTION
hardware.

3. Access the hose assembly (8, Figure 1-6) and BE CAREFUL WHEN POSITIONING THE
press on the two buttons, at the same time pull down, TA N K A S S E M B LY O N T H E C A B I N
unlock and disconnect the hose assembly from the FLOOR OR DAMAGE TO THE AFT CABIN
stowage plug (31). BULKHEAD AND PYLON ISLAND BEAM
CAN OCCUR.
4. Remove the screws (12), washers (11), and cover
assembly (10) from the cabin floor. Retain the cover a. Install the seal (21) on the frangible valve (22),
assembly (10) and the hardware. as shown in View B.

ECCN EAR99 9 JAN 2012 1-25

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

BL
0.00
B
A
1
26

SEE DETAIL D
C

20
24

23

FW 21
D

AFT CABIN
19 T BULKHEAD
1
22

18 PYLON ISLAND VIEW B

BEAM LOOKING DOWN
RIGHT SIDE
17

16
2

15 3

2
13
4
14
5
STA
166.00 12 6

11

10 7 T
31 9
BL
8 BL 14.00
31.50
CABIN FLOOR
VIEW A
LOOKING INBOARD RIGHT SIDE

412_SI_91_0004a

Figure 1-6. Small Right Tank Assembly (412-706-112-104) — Installation (Sheet 1 of 2)

1-26 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

23
1 26

27
BL
28 25
14.00 DETAIL D
FUSELAGE
29 BL
SKIN
0.00
8
30
0.750 IN.
(19.1 mm)

VIEW C
LOOKING AFT

1. Small right tank assembly (412-706-112-104) 17. Aft fitting (205-062-611-102)

2. Shim (205-030-424-001) 3 Reqd 18. Washer (NAS1149D0563J)
3. Forward fitting (205-061-698-102) 19. Bolt (AN5-4A)
4. Washer (NAS1149D0463J) 20. Cap (Ref)
5. Bolt (AN4-7A) 21. Seal (214-066-063-003)
6. Washer (NAS1149D0463J) 2 Reqd 22. Frangible valve (Ref)
7. Bolt (AN4-5A) 2 Reqd 23. Hose assembly (70-061H000V070A)
8. Hose assembly (Ref) 24. Reducer (AS5174W0806)
9. Nipple assembly (Ref) 25. Plug (Ref)
10. Cover assembly (Ref) 26. Tube assembly (Ref)
11. Washer (Ref) 27. Fitting (Ref)
12. Screw (Ref) 28. Clamp (33-116-3)
13. Bolt (NAS624-6) 2 Reqd 29. Drain tube (130-038-17-34)
14. Washer (NAS1149D0432J) 2 Reqd 30. Grommet (MS35489-149)
15. Bolt (AN4-10A) 31. Stowage plug (Ref)
16. Washer (NAS1149D0416J)

25 TO 35 IN-LBS
T (2.8 TO 4.0 Nm)

412_SI_91_0004b
Figure 1-6. Small Right Tank Assembly (412-706-112-104) — Installation (Sheet 2 of 2)

ECCN EAR99 9 JAN 2012 1-27

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

b. Put the small right tank (1) in position on the

NOTE
cabin floor.
The laminated shims (2) are 0.180 inch
(4.57 mm) of total thickness, and include a
c. Route the drain tube (29) through the cabin
solid shim of 0.063 inch (1.60 mm) thick,
floor and the grommet (30). and a peelable 0.120-inch (3.05-mm)
laminated shim. Each lamination is
0.003 inch (0.08 mm) thick.
NOTE
When the two buttons are extended on the n. If necessary, shim the forward fitting (3) as
self-sealing disconnect of the hose follows:
assembly (8), it indicates that the
self-sealing disconnect is locked. (1) As necessary, peel the laminated shim
(2) to fill the gap between the small right tank
assembly (1) and the forward fitting (3).
d. Press on the two buttons of the self-sealing
disconnect and connect the hose assembly (8) to the (2) As necessary, peel the laminated shims
nipple assembly (9). Make sure the self-sealing (2) to fill the gap between the pylon island beam and
disconnect is locked. the forward fitting (3).

e. Install the aft fitting (17) on the small right tank (3) Remove the bolts (5 and 7), washers (4
assembly (1) with the bolts (13 and 15) and the and 6), and forward fitting (3) from the small right tank
washers (14 and 16). Do not tighten the bolts (13 and assembly (1).
15) at this time.
(4) Install the forward fitting (3) and the shim
(2), as applicable, on the small right tank assembly (1)
f. Temporarily install the aft fitting (17) on the with the bolt (5) and the washer (4). Tighten the bolt
cabin aft bulkhead with the bolt (19) and the washer (5).
(18). Do not tighten the bolt (19) at this time.
(5) Install the forward fitting (3) and the
g. Temporarily install the forward fitting (3) on the shims (2), as applicable, on the pylon island beam with
small right tank assembly (1) with the bolt (5) and the the bolts (7) and the washers (6). Torque the bolts
(7) T .
washer (4). Do not tighten the bolt (5) at this time.
10. Remove the plug (25) from the tube assembly
h. Temporarily install the forward fitting (3) on the (26). Retain the plug (25).
pylon island beam with the bolts (7) and the washers
(6). Do not tighten the bolts at this time. 11. Install the reducer (24) on the tube assembly
(26). Tighten the coupling nut.
i. Make sure there is no interference between
the small right tank assembly (1) and the rings (6, 12. Connect the hose assembly (23) to the
Figure 1-9). reducer (24).

j. If interference exists, move the small right tank 13. Remove the cap (20) from the frangible valve
assembly (1, Figure 1-6) to remove the interference. (22). Retain the cap (20).

14. Connect the straight end of the hose assembly

k. If there is no interference, tighten the bolts (5,
(23) to the frangible valve (22).
13, and 15) and torque the bolts (7 and 19) T .

15. To make sure there is no twisting, interference,

l. Measure the gap between the forward fitting chafing, or preloading, examine the position of the
(3) and the pylon island beam. hose assembly (23).

m. Measure the gap between the small right tank 16. Tighten the coupling nuts of the hose
assembly (1) and the forward fitting (3). assembly (23).

1-28 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

17. Install the drain tube (29) 0.75 inch (19.1 mm) 1. Remove the access panel (7, Figure 1-1) from
under the fuselage skin, as shown in View C. Make the fuselage skin. Retain all the parts.
sure the drain tube is not twisted.
2. Remove the auxiliary fuel vent cover (5) from the
18. Cut the end of the drain tube (29) at 45° and pylon island beam. Retain the cover (5) and the
make sure the bevel points aft. hardware.

19. Install the access panel (7, Figure 1-1). 3. Access the hose assembly (29, Figure 1-7), press
on the two buttons, at the same time pull down, unlock
20. Do a pressure test of the fuel system installation and disconnect the hose assembly from the stowage
as per paragraph 1-12. plug (30).

1-8. LARGE LEFT TANK ASSEMBLY 4. Remove the screws (21), washers (22), and
(412-706-112-105) — INSTALLATION cover assembly (23) from the cabin floor. Retain the
cover assembly (23) and the hardware.

WARNING 5. Install the drain tube (16) on the fitting (25) with
the clamp (15). Tighten the clamp (15).

ONLY APPROVED, EXPLOSION PROOF 6. Remove and discard the existing plug from the
TYPE LIGHTS ARE TO BE USED NEAR fuselage skin and install the grommet (17).
OPEN FUEL CELLS AND FUEL LINES.
7. If the helicopter is equipped with the Utility
Passenger Seat Installation kit (BHT-412-SI-26), do as
WARNING follows:

a. Remove the cotter pin (79, Figure 1-3), pin

OBEY ALL THE SAFETY PRECAUTIONS (77), and ring (78) from pin (80) on the cabin floor.
WHEN YOU DO MAINTENANCE ON Retain the ring (78). Discard the cotter pin (79).
FUEL SYSTEM EQUIPMENT.
b. Install the pin (77) on the pin (80) and secure
with a new cotter pin (79) on the cabin floor, as shown
NOTE
in View G.
The following procedure makes reference
to a large tank assembly. For clarification, 8. Remove the plug (20, Figure 1-7) from the tube
the large tank assembly has a capacity of assembly (24). Retain the plug (20).
81.7 U.S. gallons (309.2 L).
9. Install the reducer (18) on the tube assembly
NOTE (24). Tighten the coupling nut.
It is recommended that you do not tighten
the coupling nut on the hose assembly until 10. Connect the hose assembly (19) to the reducer
the necessary routing and orientation of the (18).
hose assembly is achieved, to prevent
twisting, interference, chafing, or 11. Remove the cap (26) from the frangible valve
preloading. (27). Retain the cap (26).

ECCN EAR99 9 JAN 2012 1-29

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

24 WL
SEE DETAIL E
63.85
19
WL
54.20 31

WL
51.10
18 26 27

A 2
3
4
5
PYLON ISLAND
BEAM SEE DETAIL D

BL 28
24 0.00
20 29
STA BL BL
166.00 14.00
BL 24.50
18.26

VIEW B
7 T 1
12 T 2 LOOKING AFT
6 14
13
5
B 10 11 21
2
22

WL
33.15 23
8
9 T 30
2

WL 28
22.00
29
1 25
DETAIL C
CABIN FLOOR 15

16 SEE DETAIL C
17 0.750 IN.
FUSELAGE SKIN (19.1 mm)
VIEW A
LOOKING INBOARD LEFT SIDE
412_SI_91_0005a
Figure 1-7. Large Left Tank Assembly (412-706-112-105) — Installation (Sheet 1 of 2)

1-30 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

1.22 IN.
(30.99 mm)
0.30 IN.
(7.62 mm) 24

0.374 TO 0.381 IN.

(9.50 TO 9.67 mm)
DIA. 1 2 20

DETAIL D DETAIL E

1. Large left tank assembly (412-706-112-105)

2. Forward fitting (412-061-032-101)
3. Washer (NAS1149F0463P)
4. Bolt (AN4-10A)
5. Shim (205-030-424-001) 3 Reqd
6. Washer (NAS1149F0463P) 2 Reqd
7. Bolt (AN4-5A) 2 Reqd
8. Washer (NAS1149F0532P)
9. Bolt (AN5-4A)
10. Washer (NAS1149F0532P)
11. Bolt (AN5-7A)
12. Bolt (AN5-4A)
13. Washer (NAS1149F0532P)
14. Aft fitting (205-061-697-001)
15. Clamp (30-116-3)
16. Drain tube (130-038-17-34)
17. Grommet (MS35489-149)
18. Reducer (AN5174W0806)
19. Hose assembly (70-061H000V060A)
20. Plug (Ref)
21. Screw (Ref)
22. Washer (Ref)
23. Cover assembly (Ref)
24. Tube assembly (Ref)
25. Fitting (Ref)
26. Cap (Ref)
27. Frangible valve (Ref)
28. Nipple assembly (Ref)
29. Hose assembly (Ref)
30. Stowage plug (Ref)
31. Seal (214-066-063-003)

25 TO 35 IN-LBS
T 1 (2.8 TO 4.0 Nm)
50 TO 70 IN-LBS
T 2 (5.6 TO 7.9 Nm)

412_SI_91_0005b
Figure 1-7. Large Left Tank Assembly (412-706-112-105) — Installation (Sheet 2 of 2)

ECCN EAR99 9 JAN 2012 1-31

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

12. Install the large left tank assembly (1) as follows: h. Temporarily install the aft fitting (14) on the
cabin aft bulkhead with the bolt (12) and the washer
(13). Do not tighten the bolt (12) at this time.

CAUTION i. Temporarily install the forward fitting (2) on the

pylon island beam with the bolts (7) and the
washers (6).
BE CAREFUL WHEN HANDLING THE
TANK ASSEMBLY. DAMAGE TO THE j. Tighten the bolts (7 and 11) and torque the
DRAIN TUBE CAN OCCUR. bolts (9 and 12) T .

k. Push with sufficient downward force on the

CAUTION large left tank assembly (1) to locate the hole in the
forward fitting (2) and hold it in position.

BE CAREFUL WHEN POSITIONING THE l. Mark the location of the hole from the large left
TA N K A S S E M B LY O N T H E C A B I N tank assembly (1) to the forward fitting (2) with a
FLOOR OR DAMAGE TO THE AFT CABIN non-permanent marker.
BULKHEAD AND PYLON ISLAND BEAM
CAN OCCUR. m. Make sure the location of the hole in the
forward fitting (2) is within the dimensions shown in
a. Install the seal (31) on the frangible valve (27), Detail D.
as shown in View B.
n. Drill one hole 0.098 inch (2.49 mm) in
b. Put the large left tank assembly (1) in position diameter through the forward fitting (2) with a No. 40
on the cabin floor. drill, as shown in Detail D.

o. Remove the bolts (7), washers (6), and

c. Route the drain tube (16) through the cabin
forward fitting (2) from the pylon island beam.
floor and the grommet (17).
p. Make sure that your drill is square with the
NOTE forward fitting (2) before opening the hole.
When the two buttons are extended on the q. Open one hole 0.374 to 0.381 inch (9.63 to
self-sealing disconnect of the hose 9.67 mm) in diameter through the forward fitting (2)
assembly (29), it indicates that the with a No. 3/8 drill.
self-sealing disconnect is locked.
r. If necessary, spot face the forward fitting (2)
d. Press on the two buttons of the self-sealing 0.625 inch (15.88 mm) in diameter with a radius of
disconnect and connect the hose assembly (29) to the 0.030 inch (0.76 mm) and a maximum depth of
nipple assembly (28). Make sure the self-sealing 0.180 inch (4.57 mm). Maintain the alignment of the
disconnect is locked. hole in the fitting and the hole in the large left tank
assembly (1).
e. Draw vertical and horizontal lines to mark the
center of the insert hole on the large left tank assembly s. Install the forward fitting (2) on the pylon
(1) with a non-permanent marker. island beam with the bolts (7) and the washers (6).

f. Connect the hose assembly (19) to the t. Install the forward fitting (2) on the large left
frangible valve (27). tank assembly (1) with the bolt (4) and the washer (3).

g. Temporarily install the aft fitting (14) on the u. Tighten the bolt (4) and torque the bolt (7) T .
large left tank assembly (1) with the bolts (9 and 11)
and the washers (8 and 10). Do not tighten the bolts (9 v. Measure the gap between the forward fitting
and 11) at this time. (2) and the large left tank assembly (1).

1-32 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

w. Measure the gap between the pylon island 1-9. LARGE RIGHT TANK ASSEMBLY
beam and the forward fitting (2). (412-706-112-106) — INSTALLATION

NOTE
WARNING
The laminated shims (5) are 0.180 inch
(4.57 mm) of total thickness, and include a
solid shim of 0.063 inch (1.60 mm) thick,
and a peelable 0.120-inch (3.05-mm) ONLY APPROVED, EXPLOSION PROOF
laminated shim. Each lamination is TYPE LIGHTS ARE TO BE USED NEAR
0.003 inch (0.08 mm) thick. OPEN FUEL CELLS AND FUEL LINES.

x. If necessary, shim the forward fitting (2) as

follows: WARNING

(1) As necessary, peel the laminated shim

(5) to fill the gap between the forward fitting (2) and the OBEY ALL THE SAFETY PRECAUTIONS
large left tank assembly (1). WHEN YOU DO MAINTENANCE ON
FUEL SYSTEM EQUIPMENT.
(2) As necessary, peel the laminated shims
(5) to fill the gap between the forward fitting (2) and the NOTE
pylon island beam.
The following procedure makes reference
(3) Remove the bolts (4 and 7), washers (3 to a large tank assembly. For clarification,
and 6), and forward fitting (2) from the large left tank the large tank assembly has a capacity of
assembly (1). 81.7 U.S. gallons (309.2 L).

(4) Install the forward fitting (2) and the shim NOTE
(5), as applicable, on the large left tank assembly (1)
It is recommended that you do not tighten
with the bolt (4) and the washer (3). Tighten the bolts.
the coupling nut on the hose assembly until
the necessary routing and orientation of the
(5) Install the forward fitting (2) and the hose assembly is achieved, to prevent
shims (5), as necessary, on the pylon island beam with twisting, interference, chafing, or
the bolts (7) and the washers (6). Torque the bolts T . preloading.

y. To make sure there is no twisting, 1. Remove the access panel (7, Figure 1-1) from
interference, chafing, or preloading, examine the the fuselage skin. Retain all the parts.
position of the hose assembly (19).
2. Remove the auxiliary fuel vent cover (5) from the
z. Tighten the coupling nuts of the hose pylon island beam. Retain the cover (5) and the
assembly (19). hardware.

13. Install the drain tube (16) 0.75 inch (19.1 mm) 3. Access the hose assembly (22), press on the two
under the fuselage skin, as shown in View A. Make buttons, at the same time pull down, unlock and
sure the drain tube is not twisted. disconnect the hose assembly from the stowage
plug (27).
14. Cut the end of the drain tube (17) at 45° and
make sure the bevel points aft. 4. Remove the screws (26, Figure 1-8), washers
(25), and cover assembly (23) from the cabin floor.
15. Install the access panel (7, Figure 1-1). Retain the cover assembly and the hardware.

16. Do a pressure test of the fuel system installation 5. Install the drain tube (19) on the fitting (31) with
as per paragraph 1-12. the clamp (18). Tighten the clamp (18).

ECCN EAR99 9 JAN 2012 1-33

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

STA
166.00 32

11 10
13 2
12 2 C
14

WL
33.15
8 T 2 3
9 4
5 T 1 WL
22.00
31
26 1
18
25 19
23

0.750 IN.
20 (19.1 mm)
27

21 VEW A
LOOKING INBOARD RIGHT SIDE
22

NO OBJECT BEYOND THIS POINT 412_SI_91_0006a

Figure 1-8. Large Right Tank Assembly (412-706-112-106) — Installation (Sheet 1 of 2)

1-34 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

BL
14.00

1.22 IN.
(30.99 mm) WL
51.10
0.30 IN.
(7.62 mm) 3
6
24
7

2
30
28
2
15
29 17 24

BL 16
0.00 BL
14.00

VIEW B VIEW C
LOOKING DOWN LOOKING AFT

1. Large right tank assembly (412-706-112-106) 17. Hose assembly (70-061H000T060A)

2. Forward fitting (412-061-032-102) 18. Clamp (33-116-3)
3. Shim (205-030-424-001) 3 Reqd 19. Tube (130-038-17-34)
4. Washer (NAS1149F0463P) 2 Reqd 20. Grommet (MS35489-149)
5. Bolt (AN4-5A) 2 Reqd 21. Nipple assembly (Ref)
6. Washer (NAS1149F0463P) 22. Hose assembly (Ref)
7. Bolt (AN4-10A) 23. Cover assembly (Ref)
8. Bolt (AN5-4A) 24. Tube assembly (Ref)
9. Washer (NAS1149F0532P) 25. Washer (Ref)
10. Aft fitting (205-061-697-001) 26. Screw (Ref)
11. Bolt (AN5-7A) 27. Stowage plug (Ref)
12. Washer (NAS1149F0532P) 28. Frangible valve (Ref)
13. Bolt (AN5-4A) 29. Cap (Ref)
14. Washer (NAS1149F0532P) 30. Reducer (AN5174W0806)
15. Seal (214-066-063-003) 31. Fitting (Ref)
16. Plug (Ref)

25 TO 35 IN-LBS
1 (28 TO 4.0 Nm)
50 TO 70 IN-LBS
2 (5.6 TO 7.9 Nm)

NO OBJECT BEYOND THIS POINT 412_SI_91_0006b

Figure 1-8. Large Right Tank Assembly (412-706-112-106) — Installation (Sheet 2 of 2)

ECCN EAR99 9 JAN 2012 1-35

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

6. Remove and discard the existing plug from the b. Put the large right tank assembly (1) in
fuselage skin and install the grommet (20). position on the cabin floor.

7. If the helicopter is equipped with the Utility c. Route the drain tube (19) through the cabin
Passenger Seat Installation kit (BHT-412-SI-26), do as floor and the grommet (20).
follows:
NOTE
a. Remove the cotter pin (79, Figure 1-3), pin
(77), and ring (78) from the pin (80) on the cabin floor. When the two buttons are extended on the
Retain the ring (78). Discard the cotter pin (79). self-sealing disconnect of the hose
assembly (22), it indicates that the
self-sealing disconnect is locked.
b. Install the pin (77) on the pin (80) and secure
with a new cotter pin (79) on the cabin floor, as shown
d. Press on the two buttons of the self-sealing
in View G.
disconnect and connect the hose assembly (22) to the
nipple assembly (21). Make sure the self-sealing
8. Remove the plug (16, Figure 1-8) from the tube disconnect is locked.
assembly (24). Retain the plug (16).
e. Draw vertical and horizontal lines to mark the
9. Install the reducer (30) on the tube assembly center of the insert hole on the large right tank
(24). Tighten the coupling nut and the reducer. assembly (1) with a non-permanent marker.

10. Connect the hose assembly (17) to the f. Connect the hose assembly (17) to the
reducer (30). frangible valve (28).

11. Remove the cap (29) from the frangible valve g. Temporarily install the aft fitting (10) on the
(28). Retain the cap (29). large right tank assembly (1) with the bolts (11 and 13)
and the washers (12 and 14). Do not tighten the bolts
(11 and 13) at this time.
12. Install the large right tank assembly (1) as
follows:
h. Temporarily install the aft fitting (10) on the aft
cabin bulkhead with the bolt (8) and the washer (9). Do
not tighten the bolt (8) at this time.
CAUTION
i. Temporarily install the forward fitting (2) on the
pylon island beam with the bolts (5) and the washers
BE CAREFUL WHEN HANDLING THE (4). Do not tighten the bolt (5) at this time.
TANK ASSEMBLY. DAMAGE TO THE
DRAIN TUBE CAN OCCUR. j. Tighten the bolts (5 and 11) and torque the
bolts (3 and 13) T .

CAUTION k. Push with sufficient downward force on the

large right tank assembly (1) to locate the hole in the
forward fitting (2) and hold it in position.
BE CAREFUL WHEN POSITIONING THE
TA N K A S S E M B LY O N T H E C A B I N l. Mark the center of the hole from the large right
FLOOR OR DAMAGE TO THE AFT CABIN tank assembly (1) to the forward fitting (2) with a
BULKHEAD AND PYLON ISLAND BEAM non-permanent marker.
CAN OCCUR.
m. Make sure the location of the hole in the
a. Install the seal (15) on the frangible valve (28), forward fitting (2) is within the dimensions shown in
as shown in View B. Detail D.

1-36 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

n. Drill one hole 0.098 inch (2.49 mm) in (3) Remove the bolts (5 and 7), washers (4
diameter through the forward fitting (2) with a No. 40 and 6), and forward fitting (2) from the large right tank
drill, as shown in View C. assembly (1).

o. Remove the bolts (5), washers (4), and (4) Install the forward fitting (2) and the shim
forward fitting (2) from the pylon island beam. (3), as applicable, on the large right tank assembly (1)
with the bolt (7) and the washer (6). Tighten the bolt
p. Make sure that your drill is square with the (7).
forward fitting (2) before opening the hole.
(5) Install the forward fitting (2) and the
q. Open one hole 0.374 to 0.381 inch (9.63 to shims (3), as applicable, on the pylon island beam with
9.67 mm) in diameter through the forward fitting (2) the bolts (5) and the washers (4). Torque the bolts
with a No. 3/8 drill. (5) T .

r. If necessary, spot face the forward fitting (2) y. To make sure there is no twisting,
0.625 inch (15.88 mm) in diameter with a radius of interference, chafing, or preloading, examine the
0.030 inch (0.76 mm) and a maximum depth of position of the hose assembly (17).
0.180 inch (4.57 mm). To maintain the alignment of the
hole in the forward fitting and the hole in the large right
z. Tighten the coupling nuts of the hose
tank assembly (1).
assembly (17).
s. Install the forward fitting (2) on the pylon island
13. Install the drain tube (19) 0.75 inch (19.1 mm)
beam with the bolts (5) and the washers (4).
under the fuselage skin, as shown in View A. Make
sure the drain tube (19) is not twisted.
t. Install the forward fitting (2) on the large right
tank assembly (1) with the bolt (7) and the washer (6).
14. Cut the end of the drain tube (17) at 45° and
u. Tighten the bolt (7) and torque the bolt (5) T . make sure the bevel points aft.

v. Measure the gap between the forward fitting 15. Install the access panel (7, Figure 1-1).
(2) and the large right tank assembly (1).
16. Do a pressure test of the fuel system installation
w. Measure the gap between the pylon island as per paragraph 1-12.
beam and the forward fitting (2).

1-9A. LARGE LEFT TANK ASSEMBLY

NOTE (412-706-112-127) — INSTALLATION
The laminated shims (3) are 0.180 inch
(4.57 mm) of total thickness, and includes a
solid shim of 0.063 inch (1.60 mm) thick, WARNING
and a peelable 0.120-inch (3.05-mm)
laminated shim. Each lamination is
0.003 inch (0.08 mm) thick.
ONLY APPROVED, EXPLOSION PROOF
x. If necessary, shim the forward fitting (2) as TYPE LIGHTS ARE TO BE USED NEAR
follows: OPEN FUEL CELLS AND FUEL LINES.

(1) As necessary, peel the laminated shim

(3) to fill the gap between the forward fitting (2) and the WARNING
large right tank assembly (1).

(2) As necessary, peel the laminated shims OBEY ALL THE SAFETY PRECAUTIONS
(3) to fill the gap between the forward fitting (2) and the WHEN YOU DO MAINTENANCE ON
pylon island beam. FUEL SYSTEM EQUIPMENT.

Export Classification C, ECCN EAR99 10 JAN 2020 Rev. 2 1-36A

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

24 WL
SEE DETAIL E
63.85
19
WL
54.20 31

WL
51.10
18 26 27

A 2
3
4
5
PYLON ISLAND
BEAM SEE DETAIL D

BL 28
24 0.00
20 29
STA BL BL
166.00 14.00
BL 24.50
18.26

VIEW B
7 T 1
12 T 2 LOOKING AFT
6 14
13
5
B 10 11 21
2
22

WL
33.15 23
8
9 T 30
2

WL 28
22.00
29
1 25
DETAIL C
CABIN FLOOR 15

16 SEE DETAIL C
17 0.750 IN.
FUSELAGE SKIN (19.1 mm)
VIEW A
LOOKING INBOARD LEFT SIDE
412_SI_91_0017a
Figure 1-8A. Large Left Tank Assembly (412-706-112-127) — Installation (Sheet 1 of 2)

1-36B Rev. 2 10 JAN 2020 Export Classification C, ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

1.22 IN.
(30.99 mm)
0.30 IN.
(7.62 mm) 24

0.374 TO 0.381 IN.

(9.50 TO 9.67 mm)
DIA. 1 2 20

DETAIL D DETAIL E

1. Large left tank assembly (412-706-112-129)

2. Forward fitting (412-061-032-101)
3. Washer (NAS1149F0463P)
4. Bolt (AN4-10A)
5. Shim (205-030-424-001) 3 Reqd
6. Washer (NAS1149F0463P) 2 Reqd
7. Bolt (AN4-5A) 2 Reqd
8. Washer (NAS1149F0532P)
9. Bolt (AN5-4A)
10. Washer (NAS1149F0532P)
11. Bolt (AN5-7A)
12. Bolt (AN5-4A)
13. Washer (NAS1149F0532P)
14. Aft fitting (205-061-697-001)
15. Clamp (30-116-3)
16. Drain tube (130-038-17-34)
17. Grommet (MS35489-149)
18. Reducer (AN5174W0806)
19. Hose assembly (70-061H000V060A)
20. Plug (Ref)
21. Screw (Ref)
22. Washer (Ref)
23. Cover assembly (Ref)
24. Tube assembly (Ref)
25. Fitting (Ref)
26. Cap (Ref)
27. Frangible valve (Ref)
28. Nipple assembly (Ref)
29. Hose assembly (Ref)
30. Stowage plug (Ref)
31. Seal (214-066-063-003)

25 TO 35 IN-LBS
T 1 (2.8 TO 4.0 Nm)
50 TO 70 IN-LBS
T 2 (5.6 TO 7.9 Nm)

412_SI_91_0017b
Figure 1-8A. Large Left Tank Assembly (412-706-112-127) — Installation (Sheet 2 of 2)

Export Classification C, ECCN EAR99 10 JAN 2020 Rev. 2 1-36C

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

9. Install the reducer (18) on the tube assembly

NOTE
(24). Tighten the coupling nut.
The following procedure makes reference
to a large tank assembly. For clarification, 10. Connect the hose assembly (19) to the reducer
the large tank assembly has a capacity of (18).
81.7 U.S. gallons (309.2 L).
11. Remove the cap (26) from the frangible valve
NOTE (27). Retain the cap (26).
It is recommended that you do not tighten
12. Install the large left tank assembly (1) as follows:
the coupling nut on the hose assembly until
the necessary routing and orientation of the
hose assembly is achieved, to prevent
twisting, interference, chafing, or CAUTION
preloading.

1. Remove the access panel (7, Figure 1-1) from BE CAREFUL WHEN HANDLING THE
the fuselage skin. Retain all the parts. TANK ASSEMBLY. DAMAGE TO THE
DRAIN TUBE CAN OCCUR.
2. Remove the auxiliary fuel vent cover (5) from the
pylon island beam. Retain the cover (5) and the
hardware. CAUTION

3. Access the hose assembly (29, Figure 1-8A),

press on the two buttons, at the same time pull down, BE CAREFUL WHEN POSITIONING THE
unlock and disconnect the hose assembly (29) from TA N K A S S E M B LY O N T H E C A B I N
the stowage plug (30). FLOOR OR DAMAGE TO THE AFT CABIN
BULKHEAD AND PYLON ISLAND BEAM
4. Remove the screws (21), washers (22), and CAN OCCUR.
cover assembly (23) from the cabin floor. Retain the
a. Install the seal (31) on the frangible valve (27),
cover assembly (23) and the hardware.
as shown in View B.

5. Install the drain tube (16) on the fitting (25) with b. Put the large left tank assembly (1) in position
the clamp (15). Tighten the clamp (15). on the cabin floor.

6. Remove and discard the existing plug from the c. Route the drain tube (16) through the cabin
fuselage skin and install the grommet (17). floor and the grommet (17).

7. If the helicopter is equipped with the Utility NOTE

Passenger Seat Installation kit (BHT-412-SI-26), do as
follows: When the two buttons are extended on the
self-sealing disconnect of the hose
assembly (29), it indicates that the
a. Remove the cotter pin (79, Figure 1-3), pin self-sealing disconnect is locked.
(77), and ring (78) from pin (80) on the cabin floor.
Retain the ring. Discard the cotter pin. d. Press on the two buttons of the self-sealing
disconnect and connect the hose assembly (29) to the
b. Install the pin (77) on the pin (80) and secure nipple assembly (28). Make sure the self-sealing
with a new cotter pin (79) on the cabin floor, as shown disconnect is locked.
in View G.
e. Draw vertical and horizontal lines to mark the
8. Remove the plug (20, Figure 1-8A) from the tube center of the insert hole on the large left tank assembly
assembly (24). Retain the plug (20). (1) with a non-permanent marker.

1-36D Rev. 2 10 JAN 2020 Export Classification C, ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

f. Connect the hose assembly (19) to the t. Install the forward fitting (2) on the large left
frangible valve (27). tank assembly (1) with the bolt (4) and the washer (3).

g. Temporarily install the aft fitting (14) on the u. Tighten the bolt (4) and torque the bolt (7) T .
large left tank assembly (1) with the bolts (9 and 11)
and the washers (8 and 10). Do not tighten the bolts (9 v. Measure the gap between the forward fitting
and 11) at this time. (2) and the large left tank assembly (1).

h. Temporarily install the aft fitting (14) on the w. Measure the gap between the pylon island
cabin aft bulkhead with the bolt (12) and the washer beam and the forward fitting (2).
(13). Do not tighten the bolt (12) at this time.

i. Temporarily install the forward fitting (2) on the NOTE

pylon island beam with the bolts (7) and the The laminated shims (5) are 0.180 inch
washers (6). (4.57 mm) of total thickness, and include a
solid shim of 0.063 inch (1.60 mm) thick,
j. Tighten the bolts (7 and 11) and torque the and a peelable 0.120-inch (3.05-mm)
bolts (9 and 12) T . laminated shim. Each lamination is
0.003 inch (0.08 mm) thick.
k. Push with sufficient downward force on the
large left tank assembly (1) to locate the hole in the x. If necessary, shim the forward fitting (2) as
follows:
forward fitting (2) and hold it in position.

l. Mark the location of the hole from the large left (1) As necessary, peel the laminated shim
(5) to fill the gap between the forward fitting (2) and the
tank assembly (1) to the forward fitting (2) with a
large left tank assembly (1).
non-permanent marker.
(2) As necessary, peel the laminated shims
m. Make sure the location of the hole in the
(5) to fill the gap between the forward fitting (2) and the
forward fitting (2) is within the dimensions shown in pylon island beam.
Detail D.
(3) Remove the bolts (4 and 7), washers (3
n. Drill one hole 0.098 inch (2.49 mm) in and 6), and forward fitting (2) from the large left tank
diameter through the forward fitting (2) with a No. 40 assembly (1).
drill, as shown in Detail D.
(4) Install the forward fitting (2) and the shim
o. Remove the bolts (7), washers (6), and (5), as necessary, on the large left tank assembly (1)
forward fitting (2) from the pylon island beam. with the bolt (4) and the washer (3). Tighten the bolt
(4).
p. Make sure that your drill is square with the
forward fitting (2) before opening the hole. (5) Install the forward fitting (2) and the
shims (5), as necessary, on the pylon island beam with
q. Open one hole 0.374 to 0.381 inch (9.63 to the bolts (7) and the washers (6). Torque the bolts
9.67 mm) in diameter through the forward fitting (2) (7) T .
with a No. 3/8 drill.
y. To make sure there is no twisting,
r. If necessary, spot face the forward fitting (2) interference, chafing, or preloading, examine the
0.625 inch (15.88 mm) in diameter with a radius of position of the hose assembly (19).
0.030 inch (0.76 mm) and a maximum depth of
0.180 inch (4.57 mm). Maintain the alignment of the z. Tighten the coupling nuts of the hose
hole in the fitting and the hole in the large left tank assembly (19).
assembly (1).
13. Install the drain tube (16) 0.75 inch (19.1 mm)
s. Install the forward fitting (2) on the pylon island under the fuselage skin, as shown in View A. Make
beam with the bolts (7) and the washers (6). sure the drain tube (16) is not twisted.

Export Classification C, ECCN EAR99 10 JAN 2020 Rev. 2 1-36E

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

14. Cut the end of the drain tube (17) at 45° and 4. Remove the screws (26, Figure 1-8B), washers
make sure the bevel points aft. (25), and cover assembly (23) from the cabin floor.
Retain the cover assembly and the hardware.
15. Install the access panel (7, Figure 1-1).
5. Install the drain tube (19) on the fitting (31) with
16. Do a pressure test of the fuel system installation the clamp (18). Tighten the clamp (18).
as per paragraph 1-12.
6. Remove and discard the existing plug from the
1-9B. LARGE RIGHT TANK ASSEMBLY fuselage skin and install the grommet (20).
(412-706-112-128) — INSTALLATION
7. If the helicopter is equipped with the Utility
Passenger Seat Installation kit (BHT-412-SI-26), do as
follows:
WARNING
a. Remove the cotter pin (79, Figure 1-3), pin
(77), and ring (78) from the pin (80) on the cabin floor.
ONLY APPROVED, EXPLOSION PROOF Retain the ring. Discard the cotter pin (79).
TYPE LIGHTS ARE TO BE USED NEAR
OPEN FUEL CELLS AND FUEL LINES. b. Install the pin (77) on the pin (80) and secure
with a new cotter pin (79) on the cabin floor, as shown
in View G.
WARNING
8. Remove the plug (16, Figure 1-8B) from the tube
assembly (24). Retain the plug (16).
OBEY ALL THE SAFETY PRECAUTIONS
WHEN YOU DO MAINTENANCE ON 9. Install the reducer (30) on the tube assembly
FUEL SYSTEM EQUIPMENT. (24). Tighten the coupling nut and the reducer (30).

NOTE 10. Connect the hose assembly (17) to the

reducer (30).
The following procedure makes reference
to a large tank assembly. For clarification,
11. Remove the cap (29) from the frangible valve
the large tank assembly has a capacity of
(28). Retain the cap (29).
81.7 U.S. gallons (309.2 L).

12. Install the large right tank assembly (1) as

NOTE follows:
It is recommended that you do not tighten
the coupling nut on the hose assembly until
the necessary routing and orientation of the
hose assembly is achieved, to prevent CAUTION
twisting, interference, chafing, or
preloading.
BE CAREFUL WHEN HANDLING THE
1. Remove the access panel (7, Figure 1-1) from TANK ASSEMBLY. DAMAGE TO THE
the fuselage skin. Retain all the parts. DRAIN TUBE CAN OCCUR.

2. Remove the auxiliary fuel vent cover (5) from the

pylon island beam. Retain the cover (5) and the
hardware. CAUTION

3. Access the hose assembly (22), press on the two

buttons, at the same time pull down, unlock and BE CAREFUL WHEN POSITIONING THE
disconnect the hose assembly from the stowage TA N K A S S E M B LY O N T H E C A B I N
plug (27). FLOOR OR DAMAGE TO THE AFT CABIN

1-36F Rev. 2 10 JAN 2020 Export Classification C, ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

BULKHEAD AND PYLON ISLAND BEAM m. Make sure the location of the hole in the
CAN OCCUR. forward fitting (2) is within the dimensions shown in
Detail D.
a. Install the seal (15) on the frangible valve (28),
as shown in View B. n. Drill one hole 0.098 inch (2.49 mm) in
diameter through the forward fitting (2) with a No. 40
b. Put the large right tank assembly (1) in drill, as shown in View C.
position on the cabin floor.
o. Remove the bolts (5), washers (4), and
c. Route the drain tube (19) through the cabin forward fitting (2) from the pylon island beam.
floor and the grommet (20).
p. Make sure that your drill is square with the
forward fitting (2) before opening the hole.
NOTE
When the two buttons are extended on the q. Open one hole 0.374 to 0.381 inch (9.63 to
self-sealing disconnect of the hose 9.67 mm) in diameter through the forward fitting (2)
assembly (22), it indicates that the with a No. 3/8 drill.
self-sealing disconnect is locked.
r. If necessary, spot face the forward fitting (2)
d. Press on the two buttons of the self-sealing 0.625 inch (15.88 mm) in diameter with a radius of
disconnect and connect the hose assembly (22) to the 0.030 inch (0.76 mm) and a maximum depth of
nipple assembly (21). Make sure the self-sealing 0.180 inch (4.57 mm). To maintain the alignment of the
disconnect is locked. hole in the forward fitting and the hole in the large right
tank assembly (1).
e. Draw vertical and horizontal lines to mark the
center of the insert hole on the large right tank s. Install the forward fitting (2) on the pylon island
assembly (1) with a non-permanent marker. beam with the bolts (5) and the washers (4).

f. Connect the hose assembly (17) to the t. Install the forward fitting (2) on the large right
frangible valve (28). tank assembly (1) with the bolt (7) and the washer (6).

g. Temporarily install the aft fitting (10) on the u. Tighten the bolt (7) and torque the bolt (5) T .
large right tank assembly (1) with the bolts (11 and 13)
and the washers (12 and 14). Do not tighten the v. Measure the gap between the forward fitting
bolts (11 and 13) at this time. (2) and the large right tank assembly (1).

h. Temporarily install the aft fitting (10) on the aft w. Measure the gap between the pylon island
cabin bulkhead with the bolt (8) and the washer (9). Do beam and the forward fitting (2).
not tighten the bolt (8) at this time.

i. Temporarily install the forward fitting (2) on the NOTE

pylon island beam with the bolts (5) and the washers The laminated shims (3) are 0.180 inch
(4). Do not tighten the bolt (5) at this time. (4.57 mm) of total thickness, and includes a
solid shim of 0.063 inch (1.60 mm) thick,
j. Tighten the bolts (5 and 11) and torque the and a peelable 0.120-inch (3.05-mm)
bolts (3 and 13) T . laminated shim. Each lamination is
0.003 inch (0.08 mm) thick.
k. Push with sufficient downward force on the
large right tank assembly (1) to locate the hole in the x. If necessary, shim the forward fitting (2) as
forward fitting (2) and hold it in position. follows:

l. Mark the center of the hole from the large right (1) As necessary, peel the laminated shim
tank assembly (1) to the forward fitting (2) with a (3) to fill the gap between the forward fitting (2) and the
non-permanent marker. large right tank assembly (1).

Export Classification C, ECCN EAR99 10 JAN 2020 Rev. 2 1-36G

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

STA
166.00 32

11 10
13 2
12 2 C
14

WL
33.15
8 T 2 3
9 4
5 T 1 WL
22.00
31
26 1
18
25 19
23

0.750 IN.
20 (19.1 mm)
27

21 VEW A
LOOKING INBOARD RIGHT SIDE
22

NO OBJECT BEYOND THIS POINT 412_SI_91_0018a

Figure 1-8B. Large Right Tank Assembly (412-706-112-128) — Installation (Sheet 1 of 2)

1-36H Rev. 2 10 JAN 2020 Export Classification C, ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

BL
14.00

1.22 IN.
(30.99 mm) WL
51.10
0.30 IN.
(7.62 mm) 3
6
24
7

2
30
28
2
15
29 17 24

BL 16
0.00 BL
14.00

VIEW B VIEW C
LOOKING DOWN LOOKING AFT

1. Large right tank assembly (412-706-112-130) 17. Hose assembly (70-061H000T060A)

2. Forward fitting (412-061-032-102) 18. Clamp (33-116-3)
3. Shim (205-030-424-001) 3 Reqd 19. Tube (130-038-17-34)
4. Washer (NAS1149F0463P) 2 Reqd 20. Grommet (MS35489-149)
5. Bolt (AN4-5A) 2 Reqd 21. Nipple assembly (Ref)
6. Washer (NAS1149F0463P) 22. Hose assembly (Ref)
7. Bolt (AN4-10A) 23. Cover assembly (Ref)
8. Bolt (AN5-4A) 24. Tube assembly (Ref)
9. Washer (NAS1149F0532P) 25. Washer (Ref)
10. Aft fitting (205-061-697-001) 26. Screw (Ref)
11. Bolt (AN5-7A) 27. Stowage plug (Ref)
12. Washer (NAS1149F0532P) 28. Frangible valve (Ref)
13. Bolt (AN5-4A) 29. Cap (Ref)
14. Washer (NAS1149F0532P) 30. Reducer (AN5174W0806)
15. Seal (214-066-063-003) 31. Fitting (Ref)
16. Plug (Ref)

25 TO 35 IN-LBS
1 (28 TO 4.0 Nm)
50 TO 70 IN-LBS
2 (5.6 TO 7.9 Nm)

NO OBJECT BEYOND THIS POINT 412_SI_91_0018b

Figure 1-8B. Large Right Tank Assembly (412-706-112-128) — Installation (Sheet 2 of 2)

Export Classification C, ECCN EAR99 10 JAN 2020 Rev. 2 1-36I/1-36J

FOR BEST VALUE, BUY GENUINE BELL PARTS
 BHT-412-SI-91

(2) As necessary, peel the laminated shims with this kit do not need to be installed and
(3) to fill the gap between the forward fitting (2) and the may be stored as necessary.
pylon island beam.
NOTE
(3) Remove the bolts (5 and 7), washers (4 The following procedure is for the restraint
and 6), and forward fitting (2) from the large right tank assemblies (12 and 13, Figure 1-9) on the
assembly (1). left side. The procedure is the same for the
restraint assemblies on the right side,
except where indicated.
(4) Install the forward fitting (2) and the shim
(3), as necessary, on the large right tank assembly (1) 1. Install the restraint assemblies (12 and 13) as
with the bolt (7) and the washer (6). Tighten the follows:
bolt (7).
a. At station 131.30, WL 78.00, install the
(5) Install the forward fitting (2) and the restraint assembly (12) on the pylon island beam (20)
shims (3), as necessary, on the pylon island beam with with the screws (11). Tighten the screws (11).
the bolts (5) and the washers (4). Torque the
bolts (5) T . b. At station 131.30, WL 63.17, install the guide
assembly (10), bushing (9), washer (8), and bolt (7).
Tighten the bolt. Make sure the roller of the guide
y. To make sure there is no twisting, assembly is above the bolt, as shown in Detail B.
interference, chafing, or preloading, examine the
position of the hose assembly (17). c. For the left side, at station 149.80, WL 78.00,
install the restraint assembly (13) on the pylon island
z. Tighten the coupling nuts of the hose beam (20) with the screws (14). Tighten the
screws (14).
assembly (17).

d. For the right side, at station 149.80, WL 78.00,

13. Install the drain tube (19) 0.75 inch (19.1 mm) install the restraint assembly (13) on the pylon island
under the fuselage skin, as shown in View A. Make beam (20) with the screws (15). Tighten the
sure the drain tube is not twisted. screws (15).

e. At station 149.80, WL 64.72, install the guide

14. Cut the end of the drain tube (17) at 45° and assembly (16), bushing (17), washer (18), and bolt
make sure the bevel points aft. (19). Tighten the bolt. Make sure the roller of the guide
assembly is above the bolt, as shown in Detail B.
15. Install the access panel (7, Figure 1-1).
f. At station 131.30, WL 63.17 and at station
149.80, WL 64.72, remove the nut (25), washer (24),
16. Do a pressure test of the fuel system installation screw (21), and spacers (22 and 23).
as per paragraph 1-12.
g. Route the shoulder harness belts from the
restraint assemblies (12 and 13) down behind the
1-10. RESTRAINT, GUIDE ASSEMBLIES, rollers of the guide assemblies (10 and 16).
AND SEAT BELTS — INSTALLATION
h. At station 131.30, Wl 63.17 and at station
149.80, WL 64.72, install the spacers (22 and 23),
NOTE screw (21), washer (24), and nut (25). Tighten the
If the helicopter is equipped with the Airline nut (25).
Seat Kit (BHT-412-SI-43), the restraints
and the guides are already installed. In this i. Attach the end of the restraint assemblies (12
case, the restraints and the guides supplied and 13) to the rings (6).

Export Classification C, ECCN EAR99 10 JAN 2020 Rev. 2 1-37

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

1-11. TANK SEAT CUSHIONS AND LIFE EMERGENCY FLOAT KIT (BHT-412-SI-2
VEST POCKETS — INSTALLATION OR BHT-412-SI-60).

NOTE
MATERIALS REQUIRED The following procedure is for the pile
installation on the left side. The procedure
Refer to BHT-ALL-SPM for specifications. is the same for the pile installation on the
right side, except where indicated.
NUMBER NOMENCLATURE
3. If the Emergency Float Kit (BHT-412-SI-2 or
C-324 Adhesive BHT-412-SI-60) is installed on the helicopter, do as
follows:

1. For the left side, install the left cushion assembly a. Mark the location of the piles (2) on the small
(3, Figure 1-9) on the small tank assembly (1). tank assembly (1) with tape to the dimension shown in
Detail A.
2. For the right side, install the right cushion
b. Cut eight pieces of pile (2) to the length shown
assembly (4) on the small tank assembly (1).
in Detail A.

c. Install the piles (2) on the small tank assembly

(1) with adhesive (C-324).
CAUTION
1-12. AUXILIARY FUEL SYSTEM —
PRESSURE TESTING
THE INSTALLATION OF THE AUXILIARY
TA N K A S S E M B LY W I T H T H E L I F E 1. Do a pressure test of the fuel provisions and all
VEST POCKET ASSEMBLIES the tank assemblies as per the instructions in the
(212-961-126-109), AT THE LOCATION BHT-412-MM-4, BHT-412-MMS-EPI or
SHOWN, IS MANDATORY WHEN THE BHT-412-MMS-EPX, Chapter 28, but do not exceed
HELICOPTER IS EQUIPPED WITH THE 0.5 PSIG (0.344 kPa) of air pressure.

1-38 Rev. 3 15 JUL 2020 Export Classification C, ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

21 22 23 24 25

UP
10
16
DETAIL B
SEE DETAIL A

15 2
STA STA
11 12 131.30 149.80 14 1
13

WL WL
78.00 78.00

7 8 9 10 16 17 18 19

WL
WL 64.72
63.17

SEE DETAIL B

20

3 4

5 6

1.0 IN. 10 IN. 3.0 IN.

(25.4 mm) (254 mm) (76.2 mm)
WL
22.00
3.0 IN. 10.5 IN.
(76.2 mm) (266.7 mm)
(2 PL)

DETAIL A 2 A 3
LEFT SIDE SHOWN (8 PLACES)
(RIGHT SIDE OPPOSITE)
412_SI_91_0007a
Figure 1-9. Tank Seat Cushions and Restraint Assembly — Installation (Sheet 1 of 2)

ECCN EAR99 9 JAN 2012 1-39

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

1. Small tank assembly (Ref) 13. Restraint assembly (412-370-711-105) 2 Reqd

2. Pile (50-029-8A080T) 16 Reqd 14. Screw (MS24694-S53) 4 Reqd
3. Left cushion assembly (412-070-836-103) 15. Screw (MS24694-S54) 4 Reqd
4. Right cushion assembly (412-070-836-104) 16. Guide Assembly (206-072-847-103) 2 Reqd
5. Washer (NAS1149F0563P) 6 Reqd 17. Bushing (NAS75-4-005) 2 reqd
6. Ring (205-070-725-001) 6 Reqd 18. Washer (NAS1149F0432P) 2 Reqd
7. Bolt (NAS6204-10) 2 Reqd 19. Bolt (NA6204-10) 2 Reqd
8. Washer (NAS1149F0432P) 2 Reqd 20. Pylon island beam (Ref)
9. Busing (NAS75-4-005) 2 Reqd 21. Screw (Ref)
10. Guide assembly (206-072-847-103) 2 Reqd 22. Spacer (Ref)
11. Screw (MS24694-S53) 8 Reqd 23. Spacer (Ref)
12. Restraint assembly (412-370-711-105) 2 Reqd 24. Washer (Ref)
25. Nut (Ref)

A ADHESIVE (C-324)

NOTES
1 For left side only.

2 For right side only.

3 Install only when an Emergency Floatation Kit (BHT-412-SI-2 or BHT-412-SI-60) is installed.

412_SI_91_0007b
Figure 1-9. Tank Seat Cushions and Restraint Assembly — Installation (Sheet 2 of 2)

1-40 9 JAN 2012 ECCN EAR99

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 BHT-412-SI-91

1-13. AUXILIARY FUEL SYSTEM — f. If not previously installed, install the

ELECTRICAL INSTALLATION transmitter (19) on top of the small right tank assembly
(5) or the small left tank assembly (9), as necessary,
1-14. SMALL TANK ASSEMBLY — ELECTRICAL as follows:
INSTALLATION
(1) Install the gasket (24) on the
transmitter (19).
NOTE
The following procedure is for the left side. (2) Put the transmitter (19) and the gasket
The procedure is the same for the right (24) in position on the small right tank assembly (5) or
side, except where indicated. the small left tank assembly (9).

1. Locate the cable assemblies (W38 and W39) (3 (3) Install the retainers (15) on the
and 8, Figure 1-10, View A). transmitter (19) with the screws (29) and the washer
(30). Tighten the screws (29).
2. For the left side, connect the connector (1P13A)
(6) at the end of the cable assembly (W39) (8) to the g. Remove the screws (27), washers (28), and
left receptacle (1J13) (7). transmitter cover (16) from the transmitter (19). Retain
the hardware.
3. For the right side, connect the connector (1P10A)
(2) at the end of cable assembly (W38) (3) to the right h. Route the cable assembly (W39) (8) or the
receptacle (1J10) (1). cable assembly (W38) (3) under the transmitter cover
(16) to the central point (23, View D).
4. As applicable, route the cable assembly (W39)
(8) or the cable assembly (W38) (3) from the i. Attach the terminal lugs at the end of the cable
receptacle (1J13) (7) or the receptacle (1J10) (1) to assembly (W39) (8) as follows:
the transmitter (1Z21 or 1Z22) (19, Section C-C and
View D), located on top of the small left tank assembly (1) Attach the terminal lug at the end of the
(9) or small right tank assembly (5), as follows: orange wire to the terminal No. 1 (20) with the
supplied screw and washer. Tighten the screw.
a. Put the three clamps (12) in position on the
cable assembly (W39) (8) or cable assembly (2) Attach the terminal lug at the end of the
(W38) (3). blue wire to the terminal No. 2 (21) with the supplied
screw and washer. Tighten the screw.
b. Install the three clamps (12) on the
transmission bulkhead assembly panel (10) nutplates (3) Attach the terminal lug at the end of the
(11), with the screws (13) and the washers (14). white wire to the terminal No. 3 (22) with the supplied
Tighten the screws (13). screw and washer. Tighten the screw.

c. Temporarily remove the cushion assembly (4) j. Install the transmitter cover (16, Section C-C)
from the small left tank assembly (9) or the small right on the transmitter (19) with the screws (27) and the
tank assembly (5). washers (28). Tighten the screws (27).

d. Remove the screws (25), washers (26), and k. Install the cover assembly (17) on the small
cover assembly (17, Section C-C) from the small left left tank assembly (9) or the small right tank assembly
tank assembly (9) or the small right tank assembly (5). (5) with the screws (25) and the washers (26). Tighten
Retain the hardware. the screws (25).

e. Feed the cable assembly (W39) (8) or the l. Install the cushion assembly (4) on the small
cable assembly (W38) (3) through the grommet (18) left tank assembly (9) or the small right tank
on the cover assembly (17). assembly (5).

ECCN EAR99 9 JAN 2012 1-41

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

2
A 7
6
1

WL
74.50

WL
60.79
3
8

WL
48.40

4 4

5 BL
22.80 9

WL
22.00

BL
14.00
BL
0.00

BL
BL 14.00 BL
24.50 24.50
VIEW A
LOOKING AFT
412_SI_91_0008a
Figure 1-10. Small Tank Assembly — Electrical Installation (Sheet 1 of 4)

1-42 9 JAN 2012 ECCN EAR99

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 BHT-412-SI-91

FS
160.00
11 12 13 14
(2 PLACES)

WL
74.50
10
3 8
FS
155.41

WL
60.79
FS
140.60

WL
48.40

5 9

WL
22.00
FS
151.10

VIEW B
LEFT SIDE SHOWN, RIGHT SIDE OPPOSITE
(PROVISION PARTS NOT SHOWN FOR CLARITY)

412_SI_91_0008b

Figure 1-10. Small Tank Assembly — Electrical Installation (Sheet 2 of 4)

ECCN EAR99 9 JAN 2012 1-43

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

FS
151.10 25
26
17 18 3 8
1 16
5 9
15

24 19

SECTION C-C
LEFT SIDE SHOWN, RIGHT SIDE OPPOSITE
ROTATED 45º CLOCKWISE

FS
151.10 27 29
23 28 30
15 19

22

20

BL 3 1
23.40

21

VIEW D
LEFT SIDE SHOWN, RIGHT SIDE OPPOSITE
(COVER ASSEMBLY NOT SHOWN FOR CLARITY)
412_SI_91_0008c
Figure 1-10. Small Tank Assembly — Electrical Installation (Sheet 3 of 4)

1-44 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

1. Receptacle (1J10) (Ref)

2. Connector (1P10A) (Ref)
3. Cable assembly (W38) (412-075-604-159)
4. Cushion assembly (Ref)
5. Small right tank assembly (Ref)
6. Connector (1P13A) (Ref)
7. Receptacle (1J13) (Ref)
8. Cable assembly (W39) (412-075-604-157)
9. Small left tank assembly (Ref)
10. Transmission bulkhead assembly panel (Ref)
11. Nutplate (Ref)
12. Clamp (MS21919WDG2) 6 Reqd
13. Screw (MS27039-1-10) 6 Reqd
14. Washer (NAS1149D0332J) 6 Reqd
15. Retainer (214-066-222-127) 4 Reqd
16. Transmitter cover (Ref)
17. Cover assembly (412-061-665-101) 2 Reqd
18. Grommet (Ref)
19. Transmitter (20048-0000-01) 2 Reqd
20. Terminal No. 1 (Ref)
21. Terminal No. 2 (Ref)
22. Terminal No. 3 (Ref)
23. Central point (Ref)
24. Gasket (406-060-606-101) 2 Reqd
25. Screw (MS27039-1-05) 8 Reqd
26. Washer (NAS1149D0316J) 8 Reqd
27. Screw (MS35206-226) 6 Reqd
28. Lockwasher (MS35338-41) 6 Reqd
29. Screw (MS27039-4-13) 8 Reqd
30. Washer (NAS1149D0416J) 8 Reqd

NOTE
1 Route the cable assemblies (W38 and W39) (3 and 8) under the transmitter cover (16)
to the central point (23).

412_SI_91_0008d

Figure 1-10. Small Tank Assembly — Electrical Installation (Sheet 4 of 4)

ECCN EAR99 9 JAN 2012 1-45

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

1-15. LARGE TANK ASSEMBLY — e. If not previously installed, install the probe (19)
ELECTRICAL INSTALLATION on top of the large right tank assembly (5) or large left
tank assembly (9), as applicable, as follows:

MATERIALS REQUIRED (1) As applicable, remove the cover

assembly (22 or 23) from the large right tank assembly
Refer to BHT-ALL-SPM for specifications. (5) or the large left tank assembly (9).

NUMBER NOMENCLATURE
(2) If not previously installed, install the plate
C-024 Assembly Fluid (25) on the large right tank assembly (5) or the large
left tank assembly (9) with the screws (26). Tighten the
screws (26).

NOTE
(3) Lubricate the packing (27) with assembly
The following procedure is for the left side. fluid (C-024).
The procedure is the same for the right
side, except where indicated.
(4) Install the packing (27) on the probe (18).
1. Locate the cable assemblies (W38 and W39) (3
and 8, Figure 1-11, View A). (5) Put the probe (18) and the packing (27)
in position on the plate (25).
2. For the left side, connect the connector (1P13A)
(6) at the end of cable assembly (W39) (8) to the (6) Install the retainers (15) on the probe (18)
receptacle (1J13) (7). with the bolts (24). Tighten the bolts (24).

3. For the right side, connect the connector (1P10A) f. Remove the cover assembly (4) from the large
(2) at the end of cable assembly (W38) (3) to the left tank assembly (9) or the large right tank
receptacle (1J10) (1). assembly (5).

g. Route the cable assembly (W39) (8) or the

4. As necessary, route the cable assembly (W39)
cable assembly (W38) (3) on top of the large left tank
(8) or the cable assembly (W38) (3) from the
assembly (9) or the large right tank assembly (5), as
receptacle (1J13) (7) or receptacle (1J10) (1) to the
shown in View D.
probe (18, Section C-C and View D), located on top of
the large left tank assembly (9) or large right tank
assembly (5), as follows: h. Put the clamp (19) in position on the cable
assembly (W39) (8) or the cable assembly (W38) (3).
a. Put the two clamps (11) in position on the
cable assembly (W39) (8, View B) or the cable i. Remove the bolt (24) at the location of the
assembly (W38) (3). clamp (19).

b. Install the two clamps (11) on the transmission j. Install the clamp (19) on the retainer (15) with
bulkhead assembly panel (10), with the existing the previously removed bolt (24). Tighten the bolt (24).
hardware. Tighten the hardware.
k. Connect the connector (1Z19P1) (16,
c. Put the clamp (12) in position on the cable Section C-C) to the receptacle (1Z19) (20) on the
assembly (W39) (8) or the cable assembly (W38) (3). probe or the connector (1Z20P1) (17) to the receptacle
(1Z20) (21) on the probe.
d. Install the clamp (12) on the transmission
bulkhead assembly panel (10) with the bolt (13) and l. Install the cover assembly (4) on the large left
washer (14). Tighten the bolt (13). tank assembly (9) or large right tank assembly (5).

1-46 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

2 6 7
1

3
8

22 4
23 4
5 9

VIEW A
LOOKING AFT

412_SI_91_0009a

Figure 1-11. Large Tank Assembly — Electrical Installation (Sheet 1 of 3)

ECCN EAR99 9 JAN 2012 1-47

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

STA
156.40
STA 11
154.05
11

3 8

10

WL
12 13 14 STA
63.85 STA
147.60
166.00

C
5 9

FWD

VIEW B
LOOKING INBOARD
LEFT SIDE SHOWN (RIGHT SIDE OPPOSITE)

412_SI_91_0009b

Figure 1-11. Large Tank Assembly — Electrical Installation (Sheet 2 of 3)

1-48 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

1. Receptacle (1J10) (Ref)

2. Connector (1P10A) (Ref)
3. Cable assembly (W38) (412-075-064-155) D
4. Cover assembly (412-070-504-101) 2 Reqd 3 8
5. Large right tank assembly (Ref) 5 9
6. Connector (1P13A) (Ref) 16 17 20 21
7. Receptacle (1J13) (Ref) 15
8. Cable assembly (W39) (412-075-064-153) 24
9. Large left tank assembly (Ref)
10. Transmission bulkhead assembly panel (Ref)
11. Clamp (AS21919WDG03Y) 4 Reqd
12. Clamp (205-706-045-9) 2 Reqd
13. Bolt (NAS6205-1) 2 Reqd 25
14. Washer (NAS1149D0516J) 2 Reqd 27
15. Retainer (214-066-065-1) 4 Reqd 18
16. Connector (1Z19P1)
17. Connector (1Z20P1)
18. Probe (20042-0000-01) 2 Reqd SECTION C-C
19. Clamp (205-706-045-7) 2 Reqd LOOKING FORWARD
20. Receptacle (1Z19) LEFT SIDE SHOWN
21. Receptacle (1Z20) (RIGHT SIDE OPPOSITE)
22. Right cover assembly (412-070-898-106)
23. Left cover assembly (412-070-898-105)
24. Bolt (MS20004-6) 8 Reqd
25. Plate (214-066-090-1) 2 Reqd 19 16 17
26. Screw (MS24694-S99) 48 Reqd STA
27. Packing (MS29513-270) 2 Reqd 166.00

ASSEMBLY FLUID (C-024)

3 8
STA
18
157.10

24 FWD

25 26

5 9

VIEW D
LOOKING DOWN
LEFT SIDE SHOWN
(RIGHT SIDE OPPOSITE)
412_SI_91_0009c_c01

Figure 1-11. Large Tank Assembly — Electrical Installation (Sheet 3 of 3)

Export Classification C, ECCN EAR99 10 JAN 2020 Rev. 2 1-49

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

1-16. RESTORATION 5. For helicopters S/N 37002 through 37999, update

the IAS configuration page (auxiliary tank)
1. Install all covers, doors, and panels previously (BHT-412-IAM-5, Section 11) and the calibration page
removed from the helicopter as per the instructions in (fuel usable capacity) (BHT-412-MMS-EPI,
Miscellaneous Access Doors and Panels Chapter 95), according to the auxiliary fuel tank
(BHT-412-MM-5, Chapter 52) to access the work configuration.
areas, as shown in Figure 1-1.
6. For helicopters S/N 38001 through 38999 or
2. If previously removed, install the left and/or right 39101 through 39999, update the IAS configuration
passenger/cargo door (BHT-412-MM-5, Chapter 52). page (auxiliary tank) (BHT-412-IAM-6, Section 11) and
the calibration page (fuel usable capacity)
(BHT-412-MMS-EPX, Chapter 95), according to the
3. Connect the battery and/or external power and
auxiliary fuel tank configuration.
close the battery access door (BHT-412-MM-10,
Chapter 96).
7. Amend the weight and balance records in
4. If Indicator Kit 412-706-112-117 is installed (S/N accordance with Chapter 2.
36087 through 36411), do a fuel quantity indicator
system calibration (BHT-412-MM-10, Chapter 96). 8. Return helicopter to the flight configuration.

1-50 Rev. 2 10 JAN 2020 Export Classification C, ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

CHAPTER 2 — OPERATION AND MAINTENANCE

TABLE OF CONTENTS

Paragraph Page
Number Title Number

2-1 Operation Procedures......................................................................................... 2-3

2-2 Maintenance Procedures .................................................................................... 2-3
2-3 Small Tank Assembly — Removal ................................................................ 2-3
2-4 Small Tank Assembly — Disassembly .......................................................... 2-7
2-5 Small Tank Assembly — Cleaning ................................................................ 2-8
2-6 Small Tank Assembly — Inspection .............................................................. 2-11
2-7 Small Tank Assembly — Repair .................................................................... 2-11
2-8 Small Tank Assembly — Assembly ............................................................... 2-11
2-9 Small Tank Assembly — Installation ............................................................. 2-13
2-10 Large Tank Assembly — Removal ................................................................ 2-15
2-11 Large Tank Assembly — Disassembly .......................................................... 2-19
2-12 Large Tank Assembly — Cleaning ................................................................ 2-19
2-13 Large Tank Assembly — Inspection .............................................................. 2-23
2-14 Large Tank Assembly — Repair.................................................................... 2-23
2-15 Large Tank Assembly — Assembly............................................................... 2-23
2-16 Large Tank Assembly — Installation ............................................................. 2-25
2-17 Weight and Balance............................................................................................ 2-27

FIGURES

Figure Page
Number Title Number

2-1 Small Tank Assembly — Removal and Installation ............................................ 2-4

2-2 Small Tank Assembly — Disassembly and Assembly........................................ 2-9
2-3 Large Tank Assembly — Removal and Installation ............................................ 2-16
2-4 Large Tank Assembly — Disassembly and Assembly........................................ 2-20

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 BHT-412-SI-91

OPERATION AND MAINTENANCE

2-1. OPERATION PROCEDURES

NOTE
Refer to the BHT-412-FMS-86.4 or the The following procedure is for the small
BHT-412-FMS-86.5 & 86.6, as applicable, for tank assembly (1, Figure 2-1) on the left
operation procedures. side. The procedure is the same for the
small tank assembly on the right side,
except where indicated.
2-2. MAINTENANCE PROCEDURES
1. Disconnect battery and external DC power from
the helicopter.
NOTE
The maintenance procedures in this 2. Remove the access panel (7, Figure 1-1) from
chapter make reference to small tank the fuselage skin.
assemblies and large tank assemblies. For
clarification, the small tank assemblies 3. Remove the left cushion assembly (3, Figure 1-9)
have a capacity of 16.3 U.S. gallons from the small left tank assembly (1).
(61.7 L) and the large tank assemblies
have a capacity of 81.7 U.S. gallons 4. Defuel the helicopter (BHT-412-MM-2,
(309.2 L). Chapter 12).

As applicable to the Universal Auxiliary Fuel Tank Kit 5. For the left side, disconnect the electrical
412-706-112, any single or combined installation of the connector (1P13A) (18, Figure 2-1) and put protective
16.3 U.S. gallon (61.7 L) small auxiliary fuel tank and caps and/or plugs (C-156) on the electrical connector
the 81.7 U.S. gallon (309.2 L) large auxiliary fuel tank (1P13A) (18).
is permitted.
6. For the right side, disconnect the electrical
Refer to BHT-412-MM-2, Chapter 5 for applicable fuel connector (1P10A) (19) and put protective caps and/or
system inspection requirements. plugs (C-156) on the electrical connector (1P10A)
(19).
2-3. SMALL TANK ASSEMBLY — REMOVAL
7. For the left side, remove the hose assembly (21)
as follows:
MATERIALS REQUIRED
a. Disconnect the hose assembly (21) from the
Refer to BHT-ALL-SPM for specifications. frangible valve (22) and put protective caps and/or
plugs (C-428) on the open port and line.
NUMBER NOMENCLATURE
b. Disconnect the hose assembly (21) from the
C-156 Caps and/or Plugs tee (23) and remove the hose assembly.

C-308 Sealant c. Install the cap (24) on the tee (23), as shown
in Detail F.
C-428 Caps and/or Plugs
8. For the right side, remove the hose assembly (25)
as follows:

WARNING a. Disconnect the hose assembly (25) from the

frangible valve (26) and put protective caps and/or
plugs (C-428) on the open port and line.
OBEY ALL THE SAFETY PRECAUTIONS
WHEN YOU DO MAINTENANCE ON b. Disconnect the hose assembly (25) and
FUEL SYSTEM EQUIPMENT. remove the hose assembly from the reducer (27).

Export Classification C, ECCN EAR99 10 JAN 2020 Rev. 2 2-3

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

BL
0.0 SEE DETAIL F FS
166.00
D

FWD
23

21
C SEE DETAIL A
1
30
22

FS
132.15

VIEW B
LEFT SIDE
18
CABIN AFT
PYLON 19 BULKHEAD
ISLAND BEAM
D 1
FW
3

T 2
11
12
10 13

7
STA
166.00
14
5
T 8 14
6
(2 PLACES)

BL E
14.00 WL
22.00 BL
FLOOR 31.05 CABIN FLOOR
DETAIL A
LOOKING INBOARD LEFT SIDE SHOWN
(RIGHT SIDE OPPOSITE)
412_SI_91_0012a
Figure 2-1. Small Tank Assembly — Removal and Installation (Sheet 1 of 3)

2-4 9 JAN 2012 ECCN EAR99

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 BHT-412-SI-91

BL
31.05 BL
SEE DETAIL G 0.00

1
29
1

WL
27
22.00
FLOOR
BL
14.00 25
6 BL 0.75 IN.
(19.0 mm) 30
18.25
FUSELAGE
20 SKIN
14
BL 26
24.50

VIEW C VIEW D
LOOKING AFT LOOKING DOWN
RIGHT SIDE

24 23

17
BL
16
18.26
BL 15
14.00
WL
29
22.00
STOWAGE
PLUG DETAIL F
6
VIEW E
LEFT SIDE SHOWN
(RIGHT SIDE OPPOSITE) 28
DETAIL G

412_SI_91_0012b
Figure 2-1. Small Tank Assembly — Removal and Installation (Sheet 2 of 3)

ECCN EAR99 9 JAN 2012 2-5

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BHT-412-SI-91

1. Small left tank assembly

2. Bolt
3. Washer
4. Aft fitting
5. Nipple assembly
6. Hose assembly
7. Forward fitting
8. Bolt
9. Washer
10. Shim
11. Cover
12. Washer
13. Screw
14. Grommet
15. Cover assembly
16. Washer
17. Screw
18. Electrical connector (1P13A)
19. Electrical connector (1P10A)
20. Drain tube
21. Hose assembly
22. Frangible valve
23. Tee
24. Cap
25. Hose assembly
26. Frangible valve
27. Reducer
28. Plug
29. Tube assembly
30. Seal

25 TO 35 IN-LBS
T (2.8 TO 3.9 Nm)

412_SI_ 91_0012c

Figure 2-1. Small Tank Assembly — Removal and Installation (Sheet 3 of 3)

2-6 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

c. Remove the reducer (27) from the hose

assembly (29). NOTE
The modified standard blankets can remain
d. Put protective caps and/or plugs (C-428) on installed on the helicopter.
all open ports and lines.
19. As necessary, install the previously removed,
e. Install the plug (28) on the tube assembly (29), standard blankets.
as shown in Detail G. Tighten the plug (28).
20. Install the previously removed carpet (14) on the
cabin floor.
9. Remove the bolts (8), washers (9), and shims
(10) from the forward fitting (7).
21. Install the access panel (7, Figure 1-1) on the
fuselage skin.
10. Remove the bolt (2) and the washer (3) from the
aft fitting (4). 22. If the helicopter is equipped with the Utility
Passenger Seat Installation kit (BHT-412-SI-26), do as
11. Access the hose assembly (6) and press on the follows:
two buttons, at the same time pull down, unlock and
disconnect the hose assembly from the nipple a. Remove the cotter pin (79, Figure 1-3) from
assembly (5). the pin (77).

12. Remove the small left tank assembly (1) from the b. Install the ring (78) on the pin (80) with the pin
cabin floor. (77) on the cabin floor. Secure the pin with a new
cotter pin (79).
13. Make sure the seal (30) is installed on the
frangible valve (26). 23. As applicable, install the previously removed
outboard facing passenger seats, restraints, and
14. Install the cover assembly (15, Figure 2-1) on the fittings in the aft cabin area. Refer to the instructions
cabin floor with the screws (17) and the washers (16). provided in the Utility Passenger Seat Installation kit
Tighten the screws(17). (BHT-412-SI-26) or the Airline Passenger Seat Kit
(BHT-412-SI-43).
NOTE 24. For helicopters S/N 37002 through 37999, update
When the two buttons are extended on the the weight and balance, fuel configuration, and fuel
self-sealing disconnect of the hose calibration page according to the BHT-412-IAM-5,
assembly (6), it indicates that the Section 11 and the BHT-412-MMS-EPI, Chapter 95.
self-sealing disconnect is locked.
25. For helicopters S/N 38001 through 38999 and
15. Press on the two buttons of the self-sealing S/N 39101 through 39999, update the weight and
disconnect and connect the hose assembly (6) to the balance, fuel configuration, and fuel calibration page
stowage plug. Make sure the self-sealing disconnect is according to the BHT-412-IAM-6, section 11 and the
locked. BHT-412-MMS-EPX, Chapter 95.

2-4. SMALL TANK ASSEMBLY —

16. Install the cover (11) on the pylon island beam
DISASSEMBLY
with the screws (13) and the washers (12), as shown
in Figure 2-1. Tighten the screws (13).
MATERIALS REQUIRED
17. Remove the grommet (14) and wet install a plug Refer to BHT-ALL-SPM for specifications.
button 100-046S48A1 with sealant (C-308) on the
fuselage skin. Retain the grommet (14). NUMBER NOMENCLATURE

18. Install the pieces of the deluxe interior blankets (1 C-156 Caps and/or Plugs
and 2, Figure 1-2) on the pylon island beam and the
C-428 Caps and/or Plugs
aft cabin bulkhead, respectively.

Export Classification C, ECCN EAR99 10 JAN 2020 Rev. 2 2-7

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

8. Remove the seal (44) from the frangible

WARNING valve (45).

9. Remove the screws (43) from the tank

OBEY ALL THE SAFETY PRECAUTIONS assembly (30).
WHEN YOU DO MAINTENANCE ON
FUEL SYSTEM EQUIPMENT.
10. Remove the screws (24), washers (25), and
spacer (26) from the tank assembly (30).

CAUTION
11. Remove the fuel cell (29) from the tank
assembly (30).
DO NOT HANDLE FUEL CELL WHEN
AMBIENT TEMPERATURE IS BELOW
12. Remove the bolts (23), washers (22), nipple
65°F (18°C).
assembly (27), and packing (28) from the fuel cell (29).
Discard the packing (28).
NOTE
The following procedure is for the small 13. Remove the bolts (48), washers (47), fitting
tank assembly (1, Figure 2-2) on the left assembly (39), and packing (46) from the fuel cell (29).
side. The procedure is the same for the Discard the packing (46).
small tank assembly on the right side,
except where indicated.
14. If necessary, remove the retainers (41) and the
washers (42) from the fitting assembly (39).
1. On top of the small left tank assembly (1), remove
the screws (5), washers (4), and cover assembly (3)
from the panel assembly (2). 15. If necessary, pull and remove the frangible valve
(45) and the packing (40) from the fitting assembly
2. If necessary, remove the grommet (6) from the (39). Discard the packing (40).
cover assembly (3).
16. If necessary, remove the bolts (17 and 18),
3. Remove the screws (7), washers (8), retainers washers (16 and 19), and aft fitting (15) from the tank
(9), transmitter (10), and gasket (11) from the panel assembly (30).
assembly (2). Discard the gasket (11).
17. If necessary, remove the bolt (33), washer (32),
4. Remove the clamp (20) and the drain tube (21) forward fitting (34), and shim (31) from the tank
from the fitting located at the bottom of the small left assembly (30).
tank assembly (1).

2-5. SMALL TANK ASSEMBLY — CLEANING

5. Remove the screws (12 and 38), washers (13
and 37), and panel assembly (2) from the tank
assembly (30).
MATERIALS REQUIRED
6. Remove the screws (36), cover assembly (35),
Refer to BHT-ALL-SPM for specifications.
and packing (14) from the fuel cell (29). Discard the
packing (14). NUMBER NOMENCLATURE

7. Remove (unlace) the nylon cord from the hangers C-305 Aliphatic Naphtha
of the fuel cell (29) and the retainers of the tank
C-339 Ethyl Alcohol
assembly (30).

2-8 9 JAN 2012 ECCN EAR99

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 BHT-412-SI-91

6 5 T 1
4
3

8
7 T 2

9
12
2
10 13
SEE DETAIL A
11

38
37
(53 PLACES)
HANGER RETAINER

36 1
35

14
1
29
LACING CORD

15
16
17
SEE DETAIL B

19
18
FITTING 2 PL
34
28
20
21
27
31
33 32
26 22

25 23 1

1 24

30

DETAIL A

412_SI_91_0013a

Figure 2-2. Small Tank Assembly — Disassembly and Assembly (Sheet 1 of 2)

ECCN EAR99 9 JAN 2012 2-9

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

43 T 2
41 T 2 (2 PLACES)
42 (2 PLACES)
44
45 40
48 1 (3 PLACES)
30 47

39
46
DETAIL B

1. Small left tank assembly 25. Washer

2. Panel assembly 26. Spacer
3. Cover assembly 27. Nipple assembly
4. Washer 28. Packing
5. Screw 29. Fuel cell
6. Grommet 30. Tank assembly
7. Screw 31. Shim
8. Washer 32. Washer
9. Retainer 33. Bolt
10. Transmitter 34. Forward fitting
11. Gasket 35. Cover assembly
12. Screw 36. Screw
13. Washer 37. Washer
14. Packing 38. Screw
15. Aft fitting 39. Fitting assembly
16. Washer 40. Packing
17. Bolt 41. Retainer
18. Bolt 42. Washer
19. Washer 43. Screw
20. Clamp 44. Seal
21. Drain tube 45. Frangible valve
22. Washer 46. Packing
23. Bolt 47. Washer
24. Screw 48. Bolt

ASSEMBLY FLUID (C-024)

7 TO 12 IN-LBS
T 1 (0.8 TO 1.35 Nm)

25 TO 35 IN-LBS
T 2 (2.8 TO 3.9 Nm)

NOTE
1 Torque the bolts or screws to the torque value specified on the fuel cell (29).
412_SI_91_0013b
Figure 2-2. Small Tank Assembly — Disassembly and Assembly (Sheet 2 of 2)

2-10 9 JAN 2012 ECCN EAR99

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 BHT-412-SI-91

5. Visually examine the tank assembly (30) for

dents, unbonded skin, and for condition. Repair or
CAUTION
replace as necessary.

WHEN USING HOT WATER TO CLEAN 2-7. SMALL TANK ASSEMBLY — REPAIR
FUEL CELL, WATER TEMPERATURE
SHALL NOT EXCEED 160°F (71°C). DO
NOT USE SOAPS OR STRONG NOTE
DETERGENTS WHEN CLEANING FUEL Refer to General Information Letter (IL)
CELL. CERTAIN STRONG DETERGENTS GEN-04-98 for the applicable shipping
ARE HARMFUL TO FUEL CELL. SOAPS information and to obtain a Return Material
CAN REACT WITH FUEL TO FORM A Authorization (RMA) number.
COMPOUND THAT CAN PLUG FUEL
FILTERS. 1. Field repair of the fuel cell (29, Figure 2-2) is not
authorized. Return the part to Bell Helicopter Textron
DO NOT USE MEK OR SIMILAR (BHT) for evaluation and possible repair.
S O LV E N T S F O R C L E A N I N G F U E L
CELLS. 2-8. SMALL TANK ASSEMBLY — ASSEMBLY

1. Clean the fuel cell (29, Figure 2-2) as follows:

MATERIALS REQUIRED
a. Remove all fungus growth from cell by hand or
with a soft scrub brush using warm water. Refer to BHT-ALL-SPM for specifications.

NUMBER NOMENCLATURE
b. If fungus is observed in cell cavity, wipe cell
cavity with clean cloths moistened with ethyl alcohol C-024 Assembly Fluid
(C-339).
C-408 Talcum Powder

2. Clean the tank assembly (29) with aliphatic C-428 Caps and/or Plugs
naphtha (C-305).
C-471 Lacing Cord

2-6. SMALL TANK ASSEMBLY — INSPECTION

1. Visually examine the fuel cell (29, Figure 2-2) for WARNING
cracks, scuffing, and general condition.

OBEY ALL THE SAFETY PRECAUTIONS

2. Visually examine the threaded inserts for WHEN YOU DO MAINTENANCE ON
serviceability. Any defect that can be detected visually FUEL SYSTEM EQUIPMENT.
is not acceptable.

3. Visually examine the hoses for damage and WARNING

deterioration. Any hose that exhibits damage or
deterioration shall be replaced.
OBEY ALL THE FUEL CELL HANDLING
PRECAUTIONS DURING REMOVAL AND
4. Visually examine the removed components for INSTALLATION OR DAMAGE TO THE
damage. FUEL CELL MAY OCCUR.

ECCN EAR99 9 JAN 2012 2-11

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BHT-412-SI-91

7. Install the packing (28) in the groove on the nipple

assembly (27).
CAUTION
8. Install the nipple assembly (27) on the fuel cell
DO NOT HANDLE FUEL CELL WHEN (29) with the bolts (23) and the washers (22). Torque
AMBIENT TEMPERATURE IS BELOW the bolts (23) to the value specified on the fuel
65°F (18°C). cell (29) T .

NOTE 9. Visually examine the tank assembly (30) cavity

for cleanliness and smooth condition of surfaces.
The following procedure is for the small
tank assembly on the left side. The
procedure is the same for the small tank 10. Apply talcum powder (C-408) to the cavity
assembly on the right side, except where surfaces of the tank assembly (30).
indicated.
11. Carefully put the fuel cell (29) in the tank
assembly (30) and insert the frangible valve (45) and
NOTE
the nipple assembly (27) through their respective
The screws or bolts should be torqued to access holes.
the torque specified on the fuel cell, except
where indicated. 12. Install the spacers (26), washers (25), and screws
(24) on the tank assembly (30). Torque the screws
1. Remove all protective caps and plugs.
(24) to the value on the fuel cell (29) T .

2. If previously removed, install the frangible valve

(45, Figure 2-2) on the fitting assembly (39) as follows: 13. Install the screws (43) on the outside of the tank
assembly (30) and secure the fitting assembly (39).
Torque the screws (43) T .
a. Lubricate a new packing (40) with assembly
fluid (C-024).
14. Install the seal (44) on the frangible valve (45).
b. Install the packing (40) on the frangible
valve (45). 15. Lace and tie a single length of lacing cord (C-471)
between retainers and hangers around the top of the
c. Install the frangible valve (45) and the packing tank assembly (30) and the fuel cell (29), as shown in
(40) on the fitting assembly (39). Detail A.

d. Install the washers (42) and the retainers (41) 16. Visually examine inside the fuel cell (29) for
on the frangible valve (45). Torque the retainers evidence of foreign materials.
(41) T .

3. Lubricate a new packing (46) with assembly fluid 17. Lubricate a new packing (14) with assembly fluid
(C-024). (C-024).

4. Install the packing (46) in the groove on the fitting 18. Install the packing (14) in the groove on the fuel
assembly (39). cell (29).

5. Install the fitting assembly (39) and the packing 19. Install the cover assembly (35) on the fuel cell
(46) on the fuel cell (29) with the bolts (48) and the (29) with the screws (36). Torque the screws (36) to
washers (47). Torque the bolts (48) to the value the value on the fuel cell T .
specified on the fuel cell (29) T .
20. Install the panel assembly (2) on the tank
6. Lubricate a new packing (28) with assembly fluid assembly (30) with the screws (12 and 38) and the
(C-024). washers (13 and 37). Tighten the screws (12 and 38).

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 BHT-412-SI-91

21. Install the drain tube (21) and the clamp (20) on
the fitting located at the bottom of the small left tank WARNING
assembly (1). Make sure the bevel points aft.

22. Tighten the clamp (20). OBEY ALL THE SAFETY PRECAUTIONS
WHEN YOU DO MAINTENANCE ON
FUEL SYSTEM EQUIPMENT.
23. Install the gasket (11), transmitter (10), retainers
(9), washers (8), and screws (7) on the cover
assembly (35). Torque the screws (7) T . NOTE
The following procedure is for the small
tank assembly on the left side. The
24. If previously removed, install the grommet (6) on
procedure is the same for the small tank
the cover assembly (3). assembly on the right side, except where
indicated.
25. Route the cable assembly through the
grommet (6).
NOTE
It is recommended that you do not tighten
26. Install the cover assembly (3) with the screws (5) the coupling nut on the hose assembly until
and the washers (4). Torque the screws (5) T . the necessary routing and orientation of the
hose assembly is achieved, to prevent
twisting, interference, chafing, or
27. Install protective caps and/or plugs (C-428) on all
preloading.
open ports.

1. If previously installed, remove the outboard facing

28. If previously removed, install the shim (31) and passenger seats, restraints, and fittings in aft cabin
the forward fitting (34) on the tank assembly (30) with area. Refer to the instructions provided in the Utility
the bolt (33) and the washer (32). Tighten the bolt (33). Passenger Seat Installation kit (BHT-412-SI-26) or the
Airline Passenger Seat Kit (BHT-412-SI-43), as
necessary.
29. If previously removed, install the aft fitting (15) on
the tank assembly (30) with the bolts (17 and 18) and
the washers (16 and 19). Tighten the bolts (17 and 2. If the helicopter is equipped with the Utility
Passenger Seat Installation kit (BHT-412-SI-26), do as
18).
follows:

30. Do a pressure test of the small left tank

a. Remove the cotter pin (79, Figure 1-3), pin
assembly (1) as per the instructions in Chapter 1,
(77), and ring (78) from pin (80) on the cabin floor.
paragraph 1-12. Retain the ring. Discard the cotter pin (79).

2-9. SMALL TANK ASSEMBLY — b. Install the pin (77) on the pin (80) and secure
INSTALLATION with a new cotter pin (79) on the cabin floor. Retain the
ring.

WARNING 3. If the deluxe interior is installed, remove the

carpet (14, Figure 1-2) from the cabin floor.

ONLY APPROVED, EXPLOSION PROOF 4. If the deluxe interior is installed, remove the
TYPE LIGHTS ARE TO BE USED NEAR pieces of the blankets (1 and 2) from the pylon island
OPEN FUEL CELLS AND FUEL LINES. beam and the aft cabin bulkhead, as necessary.

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FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

5. Make sure the modified standard interior blankets

(4 and 5) are installed on the pylon island beam and
CAUTION
the aft cabin bulkhead.

6. Remove the access panel (7, Figure 1-1). Retain BE CAREFUL WHEN POSITIONING THE
all the parts. TA N K A S S E M B LY O N T H E C A B I N
FLOOR OR DAMAGE TO THE AFT CABIN
BULKHEAD AND PYLON ISLAND BEAM
7. Remove and discard the existing plug from the CAN OCCUR.
fuselage skin and install the grommet (14, Figure 2-1).
a. Make sure the seal (30) is installed between
the tank assembly (1) and the pylon island beam.
8. Remove the screws (13), washers (12), and
cover (11) from the pylon island beam. Retain the
b. Put the small left tank assembly (1) in position
cover (11) and the hardware.
on the cabin floor.

9. Access the hose assembly (6), press on the two c. Route the drain tube (20) through the cabin
buttons, at the same time pull down, unlock and floor and the grommet (14).
disconnect the hose assembly from the stowage plug.
NOTE

NOTE When the two buttons are extended on the

self-sealing disconnect of the hose
The stowage plug stays on the cover assembly (6), it indicates that the
assembly (15). self-sealing disconnect is locked.

10. Remove the screws (17), washers (16), and d. Press on the two buttons of the self-sealing
cover assembly (15) from the cabin floor. Retain the disconnect and connect the hose assembly (6) to the
cover assembly (15) and the hardware. nipple assembly (5). Make sure the self-sealing
disconnect is locked.

11. If the helicopter is equipped with the Utility e. Install the washers (3) and the bolts (2) on the
Passenger Seat Installation kit (BHT-412-SI-26), install aft fitting (4). Do not torque the bolts (2) at this time.
the restraint assemblies (12 and 13, Figure 1-9),
washers (5), and rings (6) on the pylon island beam.
Retain all parts for later installation. NOTE
If the shims (10) are damaged, shim the
forward fitting (7) as per the instructions in
NOTE Chapter 1.
Two persons are necessary to install the f. Install the shims (10), washers (9), and bolts
small left tank assembly. (8) on the forward fitting (7).

12. Install the small left tank assembly (1, Figure 2-1) g. Torque the bolts (2 and 8) T .
as follows:
h. For the left side, install the hose assembly
(21) as follows:

CAUTION (1) Remove the cap (24) from the tee (23).
Retain the cap (24).

BE CAREFUL WHEN HANDLING THE (2) Remove the protective caps and/or plugs
TANK ASSEMBLY. DAMAGE TO THE from the frangible valve (22) and the hose
DRAIN TUBE CAN OCCUR. assembly (21).

2-14 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

(3) Connect the hose assembly (21) to the 19. For helicopters S/N 37002 through 37999, update
tee (23). the weight and balance, fuel configuration, and fuel
calibration page according to the BHT-412-IAM-5,
(4) Connect the hose assembly (21) to the Section 11 and the BHT-412-MMS-EPI, Chapter 95.
frangible valve (22).
20. For helicopters S/N 38001 through 38999 and
(5) To make sure there is no twisting, S/N 39101 through 39999, update the weight and
interference, chafing, or preloading, examine the balance, fuel configuration, and fuel calibration page
position of the hose assembly (21). according to the BHT-412-IAM-6, section 11 and the
BHT-412-MMS-EPX, Chapter 95.
(6) Tighten the coupling nuts of the hose
assembly (21). 2-10. LARGE TANK ASSEMBLY — REMOVAL
i. For the right side, install the hose assembly
(25) as follows: MATERIALS REQUIRED

(1) Remove the plug (28) from the tube Refer to BHT-ALL-SPM for specifications.
assembly (29). Retain the plug (28).
NUMBER NOMENCLATURE
(2) Remove the protective caps and/or plugs
from the hose assembly (25) and the frangible C-156 Caps and/or Plugs
valve (26).
C-308 Sealant
(3) Install the reducer (27) on the tube
assembly (29). Tighten the coupling nut. C-428 Caps and/or Plugs

(4) Connect the hose assembly (25) to the

reducer (27).

(5) Connect the hose assembly (25) to the WARNING

frangible valve (26).

(6) To make sure there is no twisting,

OBEY ALL THE SAFETY PRECAUTIONS
interference, chafing, or preloading, examine the
WHEN YOU DO MAINTENANCE ON
position of the hose assembly (25).
FUEL SYSTEM EQUIPMENT.
(7) Tighten the coupling nuts of the hose
assembly (25). NOTE
13. Install the drain tube (20) 0.75 inch (19.1 mm) The following procedure is for the large
under the fuselage skin, as shown in View C. Make tank assembly on the left side. The
sure the drain tube is not twisted and the bevel points procedure is the same for the large tank
aft. assembly on the right side, except where
indicated.
14. Install the access panel (7, Figure 1-1).
1. Disconnect battery and external DC power from
15. For the left side, remove the protective caps and/ the helicopter.
or plugs and connect the electrical connector (1P13A)
(18, Figure 2-1). 2. Remove the cover (7, Figure 1-1) from the
fuselage skin.
16. For the right side, remove the protective caps
and/or plugs and connect the electrical connector
(1P10A) (19). 3. Defuel the helicopter (BHT-412-MM-2,
Chapter 12).
17. Install the seat cushion (2, Figure 1-9) on the
small left tank assembly (1, Figure 2-1). 4. For the left side, disconnect the electrical
connector (1P13A) (9, Figure 2-3) and put protective
18. Do a pressure test of the fuel system installation caps and/or plugs (C-156) on the electrical connector
as per the instructions in Chapter 1, paragraph 1-12. (1P13A) (9).

Export Classification C, ECCN EAR99 10 JAN 2020 Rev. 2 2-15

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

A
9
10

7 8 STA
6
B 166.00

T 1 3
4 12 T 2
5 11
13
PYLON
ISLAND 2
BEAM

WL
33.15

WL
22.00
1

FWD CABIN FLOOR

14
15 FUSELAGE SKIN
VIEW A
LOOKING INBOARD
LEFT SIDE SHOWN
(RIGHT SIDE OPPOSITE)

412_SI_91_0014a
Figure 2-3. Large Tank Assembly — Removal and Installation (Sheet 1 of 2)

2-16 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

WL
BL 16 63.85 22
BL
0.00 25 23
18 18.26
WL CABIN FLOOR BL 24
27 26
54.20 14.00

WL
51.10 28
SEE 19
21
DETAIL D
29 1
DETAIL C
LEFT SIDE SHOWN
(RIGHT SIDE OPPOSITE)

SEE DETAIL C
PYLON ISLAND
BEAM

16
CABIN
FLOOR
20
21 FUSELAGE
SKIN
BL 0.75 IN.
BL (19 mm) 17
14.00 24.50
BL
18.26 DETAIL D
VIEW B
LOOKING AFT
LEFT SIDE SHOWN
(RIGHT SIDE OPPOSITE)

1. Large left tank assembly 15. Grommet

2. Forward fitting 16. Tube assembly
3. Bolt 17. Plug
4. Washer 18. Hose assembly
5. Shim 19. Frangible valve
6. Cover assembly 20. Nipple assembly
7. Washer 21. Hose assembly
8. Screw 22. Screw
9. Electrical connector (1P13A) 23. Washer
10. Electrical connector (1P10A) 24. Cover assembly
11. Aft Fitting 25. Reducer
12. Bolt 26. Cover assembly
13. Washer 27. Cover assembly
14. Drain tube 28. Stowage plug
29. Seal
25 TO 35 IN-LBS
T 1 (2.8 TO 3.9 Nm)
50 TO 70 IN-LBS
T 2 (5.6 TO 7.9 Nm)
412_SI_91_0014b

Figure 2-3. Large Tank Assembly — Removal and Installation (Sheet 2 of 2)

ECCN EAR99 9 JAN 2012 2-17

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

5. For the right side, disconnect the electrical 12. Remove the seal (29) from the frangible
connector (1P10A) (10) and put protective caps and/or valve (19).
plugs (C-156) on the electrical connector (1P10A)
(10).
13. Install the cover assembly (24) on the cabin floor
with the screws (22) and the washers (23). Tighten the
6. Remove the cover assemblies (26 and 27) from screws (22).
the top of the large left tank assembly (1).

7. Remove the hose assembly (18) as follows: NOTE

When the two buttons are extended on the
a. Disconnect the hose assembly (18) from the self-sealing disconnect of the hose
frangible valve (19) and put protective caps and/or assembly, it indicates that the self-sealing
plugs (C-428) on the open ports and lines. disconnect is locked.

b. Disconnect the hose assembly (18) from the 14. Press on the two buttons of the self-sealing
reducer (25) and remove the hose assembly. Put disconnect and connect the hose assembly (21) to the
protective caps and/or plugs (C-428) on the open ports stowage plug (28). Make sure the self-sealing
and lines. disconnect is locked.
c. Remove the reducer (25) from the tube
assembly (16). Put protective caps and/or plugs 15. Remove the grommet (15) and wet install the
(C-428) on the open ports and lines. plug button 100-046S48A1 with sealant (C-308) on the
fuselage skin. Retain the grommet (15).
d. Install the plug (17) on the tube assembly (16),
as shown in Detail D. 16. Install the access panel (7, Figure 1-1) on the
fuselage skin.
8. Remove the bolt (12) and the washer (13) from
the aft fitting (11).
17. Install the cover assembly (6, Figure 2-3) on the
pylon island beam with the screws (8) and the
9. Remove the bolts (3), washers (4), and shims (5) washers (7).
from the forward fitting (2).

10. Access the hose assembly (21) and press on the 18. Install the pieces of the deluxe interior blankets (1
two buttons, at the same time pull down, unlock and and 2, Figure 1-2) on the aft cabin bulkhead and the
disconnect the hose assembly from the nipple pylon island beam, respectively.
assembly (20).
NOTE
The modified standard blankets (4 and 5)
CAUTION can remain installed on the helicopter.

19. As applicable, install the previously removed,

BE CAREFUL WHEN YOU POSITION standard blankets.
THE TANK ASSEMBLY ON THE CABIN
FLOOR OR DAMAGE TO THE AFT CABIN
BULKHEAD AND PYLON ISLAND BEAM 20. Install the previously removed carpet (3) on the
CAN OCCUR. cabin floor.

NOTE 21. If the helicopter is equipped with the Utility

Passenger Seat Installation kit (BHT-412-SI-26), do as
Two persons are necessary to remove the follows:
large tank assembly.

11. Carefully lift and remove the large left tank a. Remove the cotter pin (79, Figure 1-3) and the
assembly (1) from the cabin floor. pin (77) from the pin (80). Discard the cotter pin (79).

2-18 Rev. 1 3 NOV 2016 Export Classification C, ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

b. Install the ring (78) on the pin (80) with the pin 5. Remove (unlace) the nylon cord from the hangers
(77) on the cabin floor. Secure the pin (80) with a new of the fuel cell (13) and the retainers of the tank
cotter pin (79). assembly (23).

22. As necessary, install the previously removed 6. Remove the screws (35), washers (36), and
outboard facing passenger seats, restraints, and spacers (37) from the tank assembly (23).
fittings in the aft cabin area. Refer to the instructions
provided in the Utility Passenger Seat Installation kit 7. Remove the seal (31) from the frangible
(BHT-412-SI-26) or the Airline Passenger Seat Kit valve (32).
(BHT-412-SI-43).
8. Remove the screws (30) from the tank
23. For helicopters S/N 37002 through 37999, update assembly (23).
the weight and balance, fuel configuration, and fuel
calibration page according to the BHT-412-IAM-5,
Section 11 and the BHT-412-MMS-EPI, Chapter 95. 9. Remove the fuel cell (13) from the tank
assembly (23).
24. For helicopters S/N 38001 through 38999 and
S/N 39101 through 39999, update the weight and 10. Remove the bolts (38), nipple assembly (39), and
balance, fuel configuration, and fuel calibration page the packing (34) from the fuel cell (13). Discard the
according to the BHT-412-IAM-6, section 11 and the packing (34).
BHT-412-MMS-EPX, Chapter 95.
11. Remove the bolts (25), washers (24), fitting
2-11. LARGE TANK ASSEMBLY — assembly (26), and the packing (33) from the fuel cell
DISASSEMBLY (13). Discard the packing (33).

12. Install caps and/or plugs (C-428) on all opening

ports.
MATERIALS REQUIRED
13. If necessary, remove the retainers (28) and the
Refer to BHT-ALL-SPM for specifications. washers (29) from the fitting assembly (26).
NUMBER NOMENCLATURE
14. If necessary, pull and remove the frangible valve
C-428 Caps and/or Plugs (32) and the packing (27) from the fitting assembly
(26). Discard the packing (27).

NOTE 15. If necessary, remove the bolts (15 and 17),

washers (16 and 18), and aft fitting (14) from the tank
The following procedure is for the large assembly (23).
tank assembly on the left side. The
procedure is the same for the large tank 16. If necessary, remove the bolt (19), washer (20),
assembly on the right side. shims (22), and forward fitting (21) from the tank
assembly (23).
1. Remove the bolts (2, Figure 2-4), clamp (3),
retainers (4), probe (5), and packing (6) from the large 2-12. LARGE TANK ASSEMBLY — CLEANING
left tank assembly (1). Discard the packing (6).

2. Remove the screws (7), washers (8) and cover MATERIALS REQUIRED
assembly (9) from the large left tank assembly (1).
Refer to BHT-ALL-SPM for specifications.
3. Remove the screws (10), plate (11), and packing
(12) from the fuel cell (13). Discard the packing (12). NUMBER NOMENCLATURE

C-305 Aliphatic Naphtha

4. Remove the clamp (41) and the drain tube (42)
from the fitting (40) located at the bottom of the tank
C-339 Ethyl Alcohol
assembly (23).

Export Classification C, ECCN EAR99 10 JAN 2020 Rev. 2 2-19

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BHT-412-SI-91

2 (4 PLACES)
3
4
4
9 7
5 8
6

SEE DETAIL A
1 10

SEE DETAIL C11

12

RETAINER

1
HANGER 13

LACING CORD

SEE DETAIL B
23
14
12 pt
21
SEE DETAIL C
22

15
T 17
2 16
18
19
20

DETAIL A
LEFT SIDE SHOWN
(RIGHT SIDE OPPOSITE)
412_SI_91_0015a

Figure 2-4. Large Tank Assembly — Disassembly and Assembly (Sheet 1 of 3)

2-20 9 JAN 2012 ECCN EAR99

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 BHT-412-SI-91

30 T 1
31
28 T 1
(2 PLACES)

29 (2 PLACES)
32 27
25 1
23
24

26 33

DETAIL B

BL
BL 14.60
34 18.26

13

23

WL
22.00
40
41
38 1 35 36 37 1
42
39

DETAIL C

412_SI_91_0015b
Figure 2-4. Large Tank Assembly — Disassembly and Assembly (Sheet 2 of 3)

ECCN EAR99 9 JAN 2012 2-21

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BHT-412-SI-91

1. Large left tank assembly

2. Bolt
3. Clamp
4. Retainer
5. Probe
6. Packing
7. Screw
8. Washer
9. Cover assembly
10. Screw
11. Plate
12. Packing
13. Fuel cell
14. Aft fitting
15. Bolt
16. Washer
17. Bolt
18. Washer
19. Bolt
20. Washer
21. Forward fitting
22. Shim
23. Tank assembly
24. Washer
25. Bolt
26. Fitting assembly
27. Packing
28. Retainer
29. Washer
30. Screw
31. Seal
32. Frangible valve
33. Packing
34. Packing
35. Screw
36. Washer
37. Spacer
38. Bolt
39. Nipple assembly
40. Fitting
41. Clamp
42. Drain tube

ASSEMBLY FLUID (C-024)

25 TO 35 IN-LBS
T 1 (2.8 TO 3.9 Nm)

50 TO 70 IN-LBS
T 2 (5.6 TO 7.9 Nm)

NOTE
1 Torque value is specified on the fuel cell (13).

412_SI_91_0015c
Figure 2-4. Large Tank Assembly — Disassembly and Assembly (Sheet 3 of 3)

2-22 9 JAN 2012 ECCN EAR99

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 BHT-412-SI-91

5. Visually examine the tank assembly (23) for

dents, unbonded skin, and for condition. Repair or
CAUTION
replace as necessary.

WHEN USING HOT WATER TO CLEAN 2-14. LARGE TANK ASSEMBLY — REPAIR
FUEL CELL, WATER TEMPERATURE
SHALL NOT EXCEED 160°F (71°C). DO
NOT USE SOAPS OR STRONG NOTE
DETERGENTS WHEN CLEANING FUEL Refer to General Information Letter (IL)
CELL. CERTAIN STRONG DETERGENTS GEN-04-98 for the applicable shipping
ARE HARMFUL TO FUEL CELL. SOAPS information and to obtain a Return Material
CAN REACT WITH FUEL TO FORM A Authorization (RMA) number.
COMPOUND WHICH CAN PLUG FUEL
FILTERS. 1. Field repair of the fuel cell (13, Figure 2-4) is not
authorized. Return the part to Bell Helicopter Textron
DO NOT USE MEK OR SIMILAR (BHT) for evaluation and possible repair.
S O LV E N T S F O R C L E A N I N G F U E L
CELLS. 2-15. LARGE TANK ASSEMBLY — ASSEMBLY

1. Clean the fuel cell (13, Figure 2-4) as follows:

MATERIALS REQUIRED
a. Remove all fungus growth from cell by hand or
with a soft scrub brush using warm water. Refer to BHT-ALL-SPM for specifications.

NUMBER NOMENCLATURE
b. If fungus is observed in cell cavity, wipe cell
cavity with clean cloths moistened with ethyl alcohol C-024 Assembly Fluid
(C-339).
C-408 Talcum Powder

2. Clean the tank assembly (23) with aliphatic C-428 Caps and/or Plugs
naphtha (C-305).
C-471 Lacing Cord

2-13. LARGE TANK ASSEMBLY — INSPECTION

1. Visually examine the fuel cell (13, Figure 2-4) for WARNING
cracks, scuffing, and general condition.

OBEY ALL THE SAFETY PRECAUTIONS

2. Visually examine the threaded inserts for WHEN YOU DO MAINTENANCE ON
serviceability. Any defect that can be detected visually FUEL SYSTEM EQUIPMENT.
is not acceptable.

3. Visually examine the hoses for damage and WARNING

deterioration. Any hose that exhibits damage or
deterioration shall be replaced.
OBEY ALL THE FUEL CELL HANDLING
PRECAUTIONS DURING REMOVAL AND
4. Visually examine the removed components for INSTALLATION OR DAMAGE TO THE
damage. FUEL CELL MAY OCCUR.

ECCN EAR99 9 JAN 2012 2-23

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BHT-412-SI-91

7. Install the packing (34) in the groove on the nipple

assembly (39).
CAUTION

8. Install the nipple assembly (39) on the fuel cell

DO NOT HANDLE FUEL CELL WHEN (13) with the bolts (38). Torque the bolts to the value
AMBIENT TEMPERATURE IS BELOW specified on the fuel cell (13) T .
65°F (18°C).
9. Visually examine the tank assembly (23) cavity
NOTE for cleanliness and smooth condition of surfaces.
The following procedure is for the large
tank assembly on the left side. The 10. Apply talcum powder (C-408) to the cavity
procedure is the same for the large tank surfaces of the tank assembly (23).
assembly on the right side, except where
indicated. 11. Carefully put the fuel cell (13) in the tank
assembly (23) and insert the frangible valve (32) and
NOTE the nipple assembly (39) through their respective
access holes.
The screws or bolts should be torqued to
the torque specified on the fuel cell, except
where indicated. 12. Install the spacers (37), washers (36), and screws
(35) on the tank assembly (23). Torque the screws
1. Remove all protective caps and plugs. (35) to the value specified on the fuel cell (13) T .

2. If previously removed, install the frangible valve 13. Install the screws (30) on the outside of the tank
(32, Figure 2-4) on the fitting assembly (26) as follows: assembly (23) to secure the fitting assembly (26).
Torque the screws (30) T .
a. Lubricate a new packing (27) with assembly
fluid (C-024). 14. Install the seal (31) on the frangible valve (32).

b. Install the packing (27) on the frangible

valve (32). 15. Lace and tie a single length of lacing cord (C-471)
between retainers and hangers around the top of the
c. Install the frangible valve (32) and the packing tank assembly (23) and the fuel cell (13), as shown in
(27) on the fitting assembly (26). Detail A.

d. Install the washers (29) and the retainers (28) 16. Visually examine inside the fuel cell (13) for
on the frangible valve (32). Torque the evidence of foreign material.
retainers (28) T .
17. Lubricate a new packing (12) with assembly fluid
3. Lubricate a new packing (33) with assembly fluid (C-024).
(C-024).

4. Install the packing (33) in the groove on the fitting 18. Install the packing (12) in the groove of the fuel
assembly (26). cell (13).

5. Install the fitting assembly (26) on the fuel cell 19. Install the plate (11) on the fuel cell (13) with the
(13) with the bolts (25) and the washers (24). Torque screws (10). Torque the screws (10) to the value
the bolts (25) to the value specified on the fuel specified on the fuel cell (13) T .
cell (13) T .
20. Install the cover assembly (9) on the tank
6. Lubricate a new packing (34) with assembly fluid assembly (23) with the screws (7) and the washers
(C-024). (8). Tighten the screws(7).

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 BHT-412-SI-91

21. Lubricate a new packing (6) with assembly fluid

(C-024). NOTE
The following procedure is for the large
tank assembly on the left side. The
22. Install the packing (6) in the groove of the
procedure is the same for the large tank
probe (5).
assembly on the right side, except where
indicated.
23. Install the probe (5), retainers (4), clamp (3), and
bolts (2) on the tank assembly (23). Tighten the NOTE
bolts (2).
It is recommended that you do not tighten
the coupling nut on the hose assembly until
24. Install the drain tube (42) and the clamp (41) on the necessary routing and orientation of the
the fitting (40) located at the bottom of the large tank hose assembly is achieved, to prevent
assembly (1). Make sure the bevel points aft. twisting, interference, chafing, or
preloading.
25. Tighten the clamp (20).
1. If previously installed, remove the outboard facing
passenger seats, restraints, and fittings in the aft cabin
26. Install protective caps and/or plugs (C-428) on all area. Refer to the instructions provided in the Utility
open ports. Passenger Seat Installation kit (BHT-412-SI-26) or the
Airline Passenger Seat Kit (BHT-412-SI-43), as
applicable.
27. If previously removed, install the aft fitting (14) on
the tank assembly (23) with the bolts (15 and 17) and
the washers (16 and 18). Torque the bolts (15 and 2. If the helicopter is equipped with the Utility
17) T . Passenger Seat Installation kit (BHT-412-SI-26), do as
follows:

28. If previously removed, install the shim (22) and a. Remove the cotter pin (79, Figure 1-3), pin
the forward fitting (21) on the tank assembly (23) with (77), and ring (78) from pin (80) on the cabin floor.
the bolt (19) and the washer (18). Torque the Retain the ring. Discard the cotter pin (79).
bolt (19) T .
b. Install the pin (77) on the pin (80) and secure
29. Do a pressure test of the large tank assembly (1) with a new cotter pin (79) on the cabin floor.
as per the instructions in Chapter 1, paragraph 1-12.
3. If the deluxe interior is installed, remove the
carpet (3, Figure 1-2) from the cabin floor.
2-16. LARGE TANK ASSEMBLY —
INSTALLATION
4. If the deluxe interior is installed, remove the
pieces of the blankets (1 and 2) from the pylon island
beam and the aft cabin bulkhead, as applicable.
WARNING
5. Make sure the modified standard interior blankets
(4 and 5) are installed on the pylon island beam and
ONLY APPROVED, EXPLOSION PROOF the aft cabin bulkhead.
TYPE LIGHTS ARE TO BE USED NEAR
OPEN FUEL CELLS AND FUEL LINES. 6. Remove the access panel (7, Figure 1-1). Retain
all the parts.

WARNING 7. Remove and discard the existing plug from the

fuselage skin and install the grommet (15, Figure 2-3).

OBEY ALL THE SAFETY PRECAUTIONS 8. Remove the screws (8), washers (7), and cover
WHEN YOU DO MAINTENANCE ON assembly (6) from the pylon island beam. Retain the
FUEL SYSTEM EQUIPMENT. cover assembly (6) and the hardware.

ECCN EAR99 9 JAN 2012 2-25

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BHT-412-SI-91

9. Access the hose assembly (21), press on the two nipple assembly (20). Make sure the self-sealing
buttons, at the same time pull down, unlock and disconnect is locked.
disconnect the hose assembly from the stowage
plug (28). e. Install the washers (13), bolts (12) on the aft
fitting (11). Do not torque the bolts (12) at this time.
10. Remove the screws (22), washers (23), and
cover assembly (24) from the cabin floor. Retain the
cover assembly (24) and the hardware. NOTE
If the shims (5) are damaged, shim the
forward fitting (2) as per the instructions in
NOTE Chapter 1.
Two persons are necessary to install the
large left tank assembly. f. Install the shims (5), washers (4), and bolts (3)
on the forward fitting (2).
11. Install the large left tank assembly (1) as follows:
g. Torque the bolts (3 and 12) T .

h. Install the hose assembly (18) as follows:

CAUTION
(1) Remove the plug (17) from the tube
BE CAREFUL WHEN HANDLING THE assembly (16). Retain the plug (17).
TANK ASSEMBLY. DAMAGE TO THE
DRAIN TUBE CAN OCCUR. (2) Remove the protective caps and/or plugs
from the hose assembly (18) and the frangible
valve (19).
CAUTION
(3) Install the reducer (25) on the tube
assembly (16). Tighten the coupling nut.
BE CAREFUL WHEN POSITIONING THE
TA N K A S S E M B LY O N T H E C A B I N (4) Connect the hose assembly (18) to the
FLOOR OR DAMAGE TO THE AFT CABIN reducer (25).
BULKHEAD AND PYLON ISLAND BEAM
CAN OCCUR. (5) Connect the hose assembly (18) to the
frangible valve (19).
a. Make sure the seal (29) is installed between
the tank assembly (1) and the pylon island beam. (6) To make sure there is no twisting,
interference, chafing, or preloading, examine the
b. Carefully put the large left tank assembly (1) in position of the hose assembly (18).
position on the cabin floor.
(7) Tighten the coupling nuts of the hose
c. Route the drain tube (14) through the cabin assembly (18).
floor and the grommet (15).
12. Install the drain tube (14) 0.75 inch (19.1 mm)
NOTE under the fuselage skin, as shown in View B. Make
sure the drain tube (14) is not twisted.
When the two buttons are extended on the
self-sealing disconnect of the hose
assembly (21), it indicates that the 13. Install the access panel (7, Figure 1-1) on the
self-sealing disconnect is locked. fuselage skin.

d. Press on the two buttons of the self-sealing 14. Install the cover assemblies (26 and 27) on top of
disconnect and connect the hose assembly (21) to the the large left tank assembly (1).

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 BHT-412-SI-91

15. For the left side, remove the protective caps and/or to the BHT-412-IAM-6, section 11 and the
plugs and connect the electrical connector (1P13A) (9). BHT-412-MMS-EPX, Chapter 95.

16. For the right side, remove the protective caps and/or 2-17. WEIGHT AND BALANCE
plugs and connect the electrical connector (1P10A) (10).
Compliance with this Service Instruction affects the
weight and balance of the helicopter as shown in the
17. Do a pressure test of the fuel system installation as
following table. Adjust ballast as necessary to return
per the instructions in Chapter 1, paragraph 1-12.
empty weight Center of Gravity (CG) to within allowable
limits (BHT-412-MM-2, Chapter 8).
18. For helicopters S/N 37002 through 37999, update
the weight and balance, fuel configuration, and fuel
calibration page according to the BHT-412-IAM-5, NOTE
Section 11 and the BHT-412-MMS-EPI, Chapter 95. This is the delta weight effect of this kit. This
includes weight and effect of the items
19. For helicopters S/N 38001 through 38999 and S/ removed when this kit is installed.
N 39101 through 39999, update the weight and balance,
fuel configuration, and fuel calibration page according

LONGITUDINAL *LATERAL

HELICOPTER KIT NUMBER WEIGHT ARM MOMENT ARM MOMENT

412 412-706-112-101 5.4 157.7 852 0.6 3

(2.4) (4006) (98.1) (15) (0.4)

412 412-706-112-103 42.6 149.1 6352 -20.7 -882

(19.3) (3787) (731.8) (-526) (-101.6)

412 412-706-112-104 42.8 149.1 6381 20.7 886

(19.4) (3787) (735.2) (526) (102.1)

412 412-706-112-105 72.8 149.0 10847 -29.1 -2118

(33.0) (3785) (1249.7) (-739) (-244.1)

412 412-706-112-106 72.8 149.0 10847 29.1 2118

(33.0) (3785) (1249.7) (739) (244.1)

412 412-706-112-117 No effect on weight and balance.

412 412-706-112-121 5.4 157.7 852 0.6 3

(2.4) (4006) (98.1) (15) (0.4)

412 412-706-112-125 5.4 157.7 852 0.6 3

(2.4) (4006) (98.1) (15) (0.4)

412 412-706-112-127 70.3 149.0 10475 -29.1 -2046

(31.9) (3785) (1206.8) (-739) (-235.7)

412 412-706-112-128 70.3 149.0 10475 29.1 2046

(31.9) (3785) (1206.8) (739) (235.7)

*In lateral calculations, - is left, + is right.

WEIGHT pounds (kilograms)

ARM inches (millimeters)

MOMENT inch•pounds  kg  mm- 

----------------------
 100 

10 JAN 2020 Rev. 2 2-27/2-28

Export Classification C, ECCN EAR99
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 BHT-412-SI-91

CHAPTER 3 — PARTS INFORMATION AND KIT INVENTORY

TABLE OF CONTENTS

Paragraph Page
Number Title Number

3-1 Parts Information................................................................................................. 3-3

3-2 Kit Inventory (412-706-112-101) ......................................................................... 3-3
3-3 Kit Inventory (412-706-112-103) ......................................................................... 3-5
3-4 Kit Inventory (412-706-112-104) ......................................................................... 3-8
3-5 Kit Inventory (412-706-112-105) ......................................................................... 3-11
3-6 Kit Inventory (412-706-112-106) ......................................................................... 3-14
3-7 Kit Inventory (412-706-112-117) ......................................................................... 3-17
3-8 Kit Inventory (412-706-112-121) ......................................................................... 3-18
3-9 Kit Inventory (412-706-112-125) ......................................................................... 3-20
3-10 Kit Inventory (412-706-112-127) ......................................................................... 3-22
3-11 Kit Inventory (412-706-112-128) ......................................................................... 3-25

Export Classification C, ECCN EAR99 15 JUL 2020 Rev. 3 3-1/3-2

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 BHT-412-SI-91

PARTS INFORMATION AND KIT INVENTORY

3-1. PARTS INFORMATION

NOTE
This chapter lists assemblies, subassemblies, and Common hardware packed with kit may
detail parts for the Universal Auxiliary Fuel Tank Kit. vary from that in following parts list. Some
items of this kit may be shipped
Part numbers in parentheses ( ) are alternate or preassembled. All modifications necessary
superseding part numbers. for field installation of this kit will be
annotated with flagnotes.

3-2. KIT INVENTORY (412-706-112-101)

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-101 Kit, Fuel Provisions, Consisting of:

1 412-706-112-113 Decal, 10-cell Fuel System

1 412-706-112-115 Decal, Nine-cell Fuel System

1 212-060-666-001 Tube Assembly

1 212-060-667-001 Tube Assembly

1 212-060-668-001 Tube Assembly

1 412-060-656-101 Tube Assembly

3 AN806-D8 Plug
(AS5168W08)

1 AS5174W0808 Union

11 MS21042L3 Nut

2 MS21919WDG10 Clamp

6 MS21919WDG18 Clamp

6 MS21919WDG22 Clamp

5 MS21919WDG8 Clamp

4 MS27039-1-08 Screw

8 MS27039-1-09 Screw

1 MS27039-1-15 Screw

2 MS29513-220 Packing

4 NAS1149D0316J Washer

10 NAS1149D0332J Washer

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QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-101 (Cont) Kit, Fuel Provisions, Consisting of:

8 NAS1149D0416J Washer

1 NAS43DD3-32N Spacer

8 NAS6604-4 Bolt

2 144020-2 Hose Assembly

2 144020-3 Cap Stowage

1 20-032-3 Bracket
(20-032-3D)

1 BHT-412-FMS-86.4 Flight Manual Supplement

1 BHT-412-SI-91 Service Instruction

3-4 Rev. 4 21 SEP 2020 Export Classification C, ECCN EAR99

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 BHT-412-SI-91

3-3. KIT INVENTORY (412-706-112-103)

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-103 Small Left Tank Kit, Consisting of:

1 412-706-112-107 Edging

1 412-706-112-109 Edging

1 1 412-706-112-119 Edging

3 205-030-424-001 Shim

1 205-061-698-101 Fitting

1 205-062-607-169 Tank Assembly

1 205-062-611-101 Fitting

3 205-070-725-001 Ring

1 205-706-044-005 Edging

2 206-072-847-103 Guide Assembly

1 214-066-061-001 Frangible Valve

1 214-066-063-003 Seal

2 214-066-064-001 Retainer

1 214-066-067-001 Support

1 214-066-070-001 Fuel Cell

1 214-066-090-101 Cover Assembly

1 214-066-093-001 Fitting Assembly

2 214-066-222-127 Retainer

1 406-060-606-101 Gasket

1 412-061-665-101 Cover Assembly

1 412-070-836-103 Cushion Assembly

1 412-075-064-157 Cable Assembly, Consisting of:

3 MS25036-102 Terminal

1 MS3476L10-6P Connector

1 M85049/31-10W Backshell

AR 100-075-5Y Plate

AR 120-080-7 Solder Sleeve

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BHT-412-SI-91

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-103 (Cont) Small Left Tank Kit, Consisting of:

1 412-075-064-157 (Cont) Cable Assembly, Consisting of:

AR 130-005-4-2 Insulation Tubing

AR 30-231-22D3 Cable

2 412-370-711-105 Restraint Assembly

1 412-961-503-105 Modification, Interior Auxiliary Fuel

1 AN4-10A Bolt

5 AN4-5A Bolt

1 AN4-7A Bolt

1 AN5-4A Bolt

3 MS21919WDG2 Clamp

8 MS24694-S53 Screw

24 MS24694-S99 Screw

8 MS27039-1-05 Screw

3 MS27039-1-10 Screw

3 MS27039-1-21 Screw

4 MS27039-4-13 Screw

1 MS29512-12 Packing

1 MS29513-114 Packing

1 MS29513-226 Packing

1 MS29513-270 Packing

3 MS35206-226 Screw

3 MS35338-41 Lockwasher

1 MS35489-149 Grommet

8 NAS1149D0316J Washer

6 NAS1149D0332J Washer

14 NAS1149D0416J Washer

2 NAS1149D0432J Washer

1 NAS1149D0563J Washer

2 NAS1149F0432P Washer

3-6 9 JAN 2012 ECCN EAR99

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 BHT-412-SI-91

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-103 (Cont) Small Left Tank Kit, Consisting of:

3 NAS1149F0563P Washer

2 NAS1189-3P8 Screw

3 NAS43DD3-51 Spacer

2 NAS624-6 Bolt

2 NAS6204-10 Bolt

4 NAS6204-6 Bolt

2 NAS75-4-005 Spacer

1 S69776 Thread

1 130-038-17-34 Tubing

1 144020-1 Nipple Assembly

1 20048-0000-01 Transmitter

1 30-116-3 Clamp

4 50-029-8A080T Pile

55 inches 50-029-12BP Pile

(139.7 cm)

55 inches 50-029-7BP Hook

(139.7 cm)

1 70-061H000V080A Hose Assembly

5 ounces 299-947-107, Type I, Adhesive (C-324)

(148 ml) Class 1

1 quart 299-947-066,Type I Adhesive (C-301)

(946 ml)

6 ounces Commercial (Pliobond 30) Adhesive

(177 ml)

15.0 feet MIL-C-5040, Type III, Nylon Cord (C-471)

(4.6 m) Color, Natural

NOTE:

1 Material, color, and style to be per helicopter sales order.

ECCN EAR99 9 JAN 2012 3-7

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

3-4. KIT INVENTORY (412-706-112-104)

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-104 Small Right Tank Kit, Consisting of:

1 412-706-112-108 Edging

1 412-706-112-109 Edging

1 1 412-706-112-119 Edging

3 205-030-424-001 Shim

1 205-061-698-102 Fitting

1 205-062-607-170 Tank Assembly

1 205-062-611-102 Fitting

3 205-070-725-001 Ring

1 205-706-044-005 Edging

2 206-072-847-103 Guide Assembly

1 214-066-061-001 Frangible Valve

1 214-066-063-003 Seal

2 214-066-064-001 Retainer

1 214-066-067-002 Support

1 214-066-070-002 Fuel Cell

1 214-066-090-101 Cover Assembly

1 214-066-093-001 Fitting Assembly

2 214-066-222-127 Retainer

1 406-060-606-101 Gasket

1 412-061-665-101 Cover Assembly

1 412-070-836-104 Cushion Assembly

1 412-075-064-159 Cable Assembly, Consisting of:

3 MS25036-102 Terminal

1 MS3476L10-6P Connector

1 M85049/31-10W Backshell

AR 100-075-5Y Plate

AR 120-080-7 Solder Sleeve

3-8 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-104 (Cont) Small Right Tank Kit, Consisting of:

1 412-075-064-159 (Cont) Cable Assembly, Consisting of:

AR 130-005-4-2 Insulation Tubing

AR 30-231-22D3 Cable

2 412-370-711-105 Restraint Assembly

1 412-961-503-106 Modification, Interior Auxiliary Fuel

1 AN4-10A Bolt

5 AN4-5A Bolt

1 AN4-7A Bolt

1 AN5-4A Bolt

1 AS5174W0806 Reducer

3 MS21919WDG2 Clamp

4 MS24694-S53 Screw

4 MS24694-S54 Screw

24 MS24694-S99 Screw

8 MS27039-1-05 Screw

3 MS27039-1-10 Screw

3 MS27039-1-21 Screw

4 MS27039-4-13 Screw

1 MS29512-12 Packing

1 MS29513-114 Packing

1 MS29513-226 Packing

1 MS29513-270 Packing

3 MS35206-226 Screw

3 MS35338-41 Lockwasher

1 MS35489-149 Grommet

8 NAS1149D0316J Washer

6 NAS1149D0332J Washer

14 NAS1149D0416J Washer

3 NAS1149D0463J Washer

ECCN EAR99 9 JAN 2012 3-9

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-104 (Cont) Small Right Tank Kit, Consisting of:

2 NAS1149D0432J Washer

2 NAS1149F0432P Washer

1 NAS1149D0563J Washer

3 NAS1149F0563P Washer

2 NAS1189-3P8 Screw

3 NAS43DD3-51 Spacer

2 NAS624-6 Bolt

2 NAS6204-10 Bolt

4 NAS6204-6 Bolt

2 NAS75-4-005 Spacer

1 S69776 Thread

1 130-038-17-34 Tubing

1 144020-1 Nipple Assembly

1 20048-0000-01 Transmitter

1 30-116-3 Clamp

4 50-029-8A080T Pile

55 inches 50-029-12BP Pile

(139.7 cm)

55 inches 50-029-7BP Hook

(139.7 cm)

1 70-061H000T070A Hose Assembly

5 ounces 299-947-107, Type I, Adhesive (C-324)

(148 ml) Class 1

1 quart 299-947-066, Type I Adhesive (C-301)

(946 ml)

6 ounces Commercial (Pliobond 30) Adhesive

(177 ml)

15.0 feet MIL-C-5040, Type III, Nylon Cord (C-471)

(4.6 m) Color, Natural

NOTE:

1 Material, color, and style to be per helicopter sales order.

3-10 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

3-5. KIT INVENTORY (412-706-112-105)

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-105 Large Left Tank Kit, Consisting of:

1 412-706-112-107 Edging

1 412-706-112-109 Edging

1 412-706-112-111 Edging

3 205-030-424-001 Shim

1 205-061-697-001 Fitting

1 205-062-606-225 Tank Assembly

1 205-706-045-007 Clamp

1 205-706-045-009 Clamp

1 214-066-061-001 Frangible Valve

1 214-066-063-003 Seal

2 214-066-064-001 Retainer

2 214-066-065-001 Retainer

1 214-066-068-001 Support

1 214-066-071-001 Fuel Cell

1 214-066-090-001 Plate

1 214-066-093-001 Fitting Assembly

1 412-061-032-101 Fitting Left

1 412-070-504-101 Cover Assembly

1 412-070-898-105 Cover Assembly

1 412-075-064-153 Cable Assembly, Consisting of:

1 MS3416-10EA Backshell

1 MS3476L10-6P Connector

1 M83723/75R1212N Connector

1 S85049/55-12W Strain Relief

AR 100-075-5Y Plate

AR 120-080-7 Solder Sleeve

AR 30-231-22-3 Cable

ECCN EAR99 9 JAN 2012 3-11

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-105 (Cont) Large Left Tank Kit, Consisting of:

1 412-961-503-101 Modification, Interior Auxiliary Fuel

1 AN4-10A Bolt

5 AN4-5A Bolt

2 AN5-4A Bolt

1 AN5-7A Bolt

1 AS5174W0806 Union

4 MS20004-6 Bolt

2 MS21919WDG3 Clamp

24 MS24694-S99 Screw

3 MS27039-1-21 Screw

1 MS29512-12 Packing

1 MS29513-114 Packing

1 MS29513-226 Packing

1 MS29513-230 Packing

1 MS29513-270 Packing

1 MS35489-149 Grommet

3 NAS1149D0332J Washer

9 NAS1149D0416J Washer

1 NAS1149D0516J Washer

3 NAS1149F0532P Washer

3 NAS1149F0563P Washer

2 NAS1189-3P6 Screw

3 NAS43DD3-51 Spacer

4 NAS6204-6 Bolt

1 NAS6205-1 Bolt

1 S69776 Thread

1 130-038-17-34 Tubing

1 144020-1 Nipple Assembly

1 20042-0000-01 Probe

3-12 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-105 (Cont) Large Left Tank Kit, Consisting of:

1 30-116-3 Clamp

1 70-061H000T060A Hose Assembly

1 quart 299-947-066, Type I Adhesive (C-301)

(946 ml)

6 ounces Commercial (Pliobond 30) Adhesive

(177 ml)

50.0 feet MIL-C-5040, Type III, Nylon Cord (C-471)

(15.2 m) Color, Natural

ECCN EAR99 9 JAN 2012 3-13

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

3-6. KIT INVENTORY (412-706-112-106)

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-106 Large Right Tank Kit, Consisting of:

1 412-706-112-108 Edging

1 412-706-112-109 Edging

1 412-706-112-111 Edging

3 205-030-424-001 Shim

1 205-061-697-001 Fitting

1 205-062-606-226 Tank Assembly

1 205-706-045-007 Clamp

1 205-706-045-009 Clamp

1 214-066-061-001 Frangible Valve

1 214-066-063-003 Seal

2 214-066-064-001 Retainer

2 214-066-065-001 Retainer

1 214-066-068-002 Support

1 214-066-071-002 Fuel Cell

1 214-066-090-001 Plate

1 214-066-093-001 Fitting Assembly

1 412-061-032-102 Fitting Right

1 412-070-504-101 Cover Assembly

1 412-070-898-106 Cover Assembly

1 412-075-064-155 Cable Assembly, Consisting of:

1 MS3416-10EA Backshell

1 MS3476L10-6P Connector

1 M83723/75R1212N Connector

1 S85049/55-12W Strain Relief

AR 100-075-5Y Plate

AR 120-080-7 Solder Sleeve

AR 30-231-22-3 Cable

3-14 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-106 (Cont) Large Right Tank Kit, Consisting of:

1 412-961-503-102 Modification, Interior Auxiliary Fuel

1 AN4-10A Bolt

5 AN4-5A Bolt

2 AN5-4A Bolt

1 AN5-6A Bolt

1 AS5174W0806 Union

4 MS20004-6 Bolt

2 MS21919WDG3 Clamp

24 MS24694-S99 Screw

3 MS27039-1-21 Screw

1 MS29512-12 Packing

1 MS29513-114 Packing

1 MS29513-226 Packing

1 MS29513-230 Packing

1 MS29513-270 Packing

1 MS35489-149 Grommet

3 NAS1149D0332J Washer

9 NAS1149D0416J Washer

1 NAS1149D0516J Washer

3 NAS1149F0532P Washer

3 NAS1149F0563P Washer

2 NAS1189-3P6 Screw

3 NAS43DD3-51 Spacer

4 NAS6204-6 Bolt

1 NAS6205-1 Bolt

1 S69776 Thread

1 130-038-17-34 Tubing

1 144020-1 Nipple Assembly

1 20042-0000-01 Probe

ECCN EAR99 9 JAN 2012 3-15

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-106 (Cont) Large Right Tank Kit, Consisting of:

1 30-116-3 Clamp

1 70-061H000T060A Hose Assembly

1 quart 299-947-066, Type I Adhesive

(946 ml)

6 ounces Commercial (Pliobond 30) Adhesive

(177 ml)

50.0 feet MIL-C-5040,Type III, Nylon Cord

(15.2 m) Color, Natural

3-16 9 JAN 2012 ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

3-7. KIT INVENTORY (412-706-112-117)

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-117 Fuel Quantity Indicator Kit, Consisting of:

1 214-175-257-109 Fuel Quantity Indicator

Export Classification C, ECCN EAR99 3 NOV 2016 Rev. 1 3-17

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

3-8. KIT INVENTORY (412-706-112-121)

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-121 Kit, Fuel Provisions, Consisting of:

1 212-060-666-001 Tube Assembly

1 212-060-667-001 Tube Assembly

1 212-060-668-001 Tube Assembly

1 412-060-656-101 Tube Assembly

1 412-706-112-113 Decal, 10-cell Fuel System

REF 412-706-112-123 Consumable Kit, Consisting of:

3.5 ounces 299-947-074, Type III, Sealant (C-328)

(103.5 ml) Class B-2

8 ounces 3950 Scotchcal Edge sealer (C-349)

(237 ml)

4 ounces Assembly Fluid No. 1 Assembly fluid (C-024)

(118 ml)

3 AS5168W08 Plug

1 AS5174W0808 Union

2 MS21919WDG10 Clamp

6 MS21919WDG18 Clamp

6 MS21919WDG22 Clamp

5 MS21919WDG8 Clamp

4 MS27039-1-08 Screw

8 MS27039-1-09 Screw

1 MS27039-1-15 Screw

2 MS29513-220 Packing

4 NAS1149D0316J Washer

10 NAS1149D0332J Washer

8 NAS1149D0416J Washer

1 NAS43DD3-32N Spacer

8 NAS6604-4 Bolt

11 NAS9926-3L Nut

3-18 Rev. 1 3 NOV 2016 Export Classification C, ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-121 (Cont) Kit, Fuel Provisions, Consisting of:

2 144020-2 Hose Assembly

2 144020-3 Stowage Plug

1 20-032-3D Bracket

1 BHT-412-FMS-86.5 Flight Manual Supplement

1 BHT-412-SI-91 Service Instruction

Export Classification C, ECCN EAR99 21 SEP 2020 Rev. 4 3-19

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

3-9. KIT INVENTORY (412-706-112-125)

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-125 Kit, Fuel Provisions, Consisting of:

1 212-060-666-001 Tube Assembly

1 212-060-667-001 Tube Assembly

1 212-060-668-001 Tube Assembly

1 412-060-656-101 Tube Assembly

REF 412-706-112-123 Consumable Kit, Consisting of:

3.5 ounces 299-947-074, Type III, Sealant (C-328)

(103.5 ml) Class B-2

8 ounces 3950 Scotchcal Edge sealer (C-349)

(237 ml)

4 ounces Assembly Fluid No. 1 Assembly fluid (C-024)

(118 ml)

3 AS5168W08 Plug

1 AS5174W0808 Union

2 MS21919WDG10 Clamp

6 MS21919WDG18 Clamp

6 MS21919WDG22 Clamp

5 MS21919WDG8 Clamp

4 MS27039-1-08 Screw

8 MS27039-1-09 Screw

1 MS27039-1-15 Screw

2 MS29513-220 Packing

4 NAS1149D0316J Washer

10 NAS1149D0332J Washer

8 NAS1149D0416J Washer

1 NAS43DD3-32N Spacer

8 NAS6604-4 Bolt

11 NAS9926-3L Nut

2 144020-2 Hose Assembly

3-20 Rev. 4 21 SEP 2020 Export Classification C, ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-125 (Cont) Kit, Fuel Provisions, Consisting of:

2 144020-3 Stowage Cap

1 20-032-3D Bracket

1 BHT-412-FMS-86.5 Flight Manual Supplement

1 BHT-412-SI-91 Service Instruction

Export Classification C, ECCN EAR99 21 SEP 2020 Rev. 4 3-21

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

3-10. KIT INVENTORY (412-706-112-127)

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-127 Large Left Tank Kit, Consisting of:

1 130-038-17-34 Tubing

3 205-030-424-001 Shim

1 205-061-697-001 Fitting

1 205-706-045-009 Clamp

1 214-066-063-003 Seal

1 30-116-3 Clamp

1 412-061-032-101 Fitting Left

1 412-070-504-101 Cover Assembly

1 412-070-898-105 Cover Assembly

1 412-075-064-153 Cable Assembly, Consisting of:

1 MS3416-10EA Backshell

1 MS3476L10-6P Connector

1 M83723/75R1212N Connector

1 S85049/55-12W Strain Relief

AR 100-075-5Y Plate

AR 120-080-7 Solder Sleeve

AR 30-231-22-3 Cable

1 412-706-112-107 Edging

1 412-706-112-109 Edging

1 412-706-112-111 Edging

1 412-706-112-129 Large Left Tank Assembly, Consisting of:

1 144020-1 Nipple Assembly

1 20042-0000-01 Probe

1 205-062-606-225 Tank Assembly

1 205-706-045-007 Clamp

1 214-066-061-001 Frangible Valve

2 214-066-064-001 Retainer

3-22 Rev. 3 15 JUL 2020 Export Classification C, ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-127 (Cont) Large Left Tank Kit, Consisting of:

1 412-706-112-129 (Cont) Large Left Tank Assembly, Consisting of:

2 214-066-065-001 Retainer

1 214-066-068-001 Support

1 214-066-071-101 Fuel Cell

1 214-066-090-001 Plate

1 214-066-093-001 Fitting Assembly

3 AN4-5A Bolt

4 MS20004-6 Bolt

24 MS24694-S99 Screw

3 MS27039-1-21 Screw

1 MS29512-12 Packing

1 MS29513-114 Packing

1 MS29513-226 Packing

1 MS29513-230 Packing

1 MS29513-270 Packing

3 NAS1149D0332J Washer

9 NAS1149D0416J Washer

2 NAS1189-3P6 Screw

3 NAS43DD3-51N Spacer

4 NAS6204-6 Bolt

AR 299-947-066, Type I Adhesive (C-301)

1 412-961-503-101 Modification, Interior Auxiliary Fuel

1 70-061H000T060A Hose Assembly

1 AN4-10A Bolt

2 AN4-5A Bolt

2 AN5-4A Bolt

1 AN5-7A Bolt

2 AS21919WDG03Y Clamp

Export Classification C, ECCN EAR99 15 JUL 2020 Rev. 3 3-23

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-127 (Cont) Large Left Tank Kit, Consisting of:

1 AS5174W0806 Union

1 MS35489-149 Grommet

1 NAS1149D0516J Washer

3 NAS1149F0463P Washer

3 NAS1149F0532P Washer

1 NAS6205-1 Bolt

AR A-A-59826, Type II, Thread

Class A, Size E

1 BHT-412-SI-91 Service Instruction

3-24 Rev. 3 15 JUL 2020 Export Classification C, ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

3-11. KIT INVENTORY (412-706-112-128)

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-128 Large Right Tank Kit, Consisting of:

1 130-038-17-34 Tubing

3 205-030-424-001 Shim

1 205-061-697-001 Fitting

1 205-706-045-009 Clamp

1 214-066-063-003 Seal

1 30-116-3 Clamp

1 412-061-032-102 Fitting Right

1 412-070-504-101 Cover Assembly

1 412-070-898-106 Cover Assembly

1 412-075-064-155 Cable Assembly, Consisting of:

1 MS3416-10EA Backshell

1 MS3476L10-6P Connector

1 M83723/75R1212N Connector

1 S85049/55-12W Strain Relief

AR 100-075-5Y Plate

AR 120-080-7 Solder Sleeve

AR 30-231-22-3 Cable

1 412-706-112-108 Edging

1 412-706-112-109 Edging

1 412-706-112-111 Edging

1 412-706-112-130 Large Right Tank Assembly, Consisting of:

1 144020-1 Nipple Assembly

1 20042-0000-01 Probe

1 205-062-606-226 Tank Assembly

1 205-706-045-007 Clamp

1 214-066-061-001 Frangible Valve

2 214-066-064-001 Retainer

Export Classification C, ECCN EAR99 15 JUL 2020 Rev. 3 3-25

FOR BEST VALUE, BUY GENUINE BELL PARTS
BHT-412-SI-91

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-128 (Cont) Large Right Tank Kit, Consisting of:

1 412-706-112-130 (Cont) Large Right Tank Assembly, Consisting of:

2 214-066-065-001 Retainer

1 214-066-068-002 Support

1 214-066-071-102 Fuel Cell

1 214-066-090-001 Plate

1 214-066-093-001 Fitting Assembly

3 AN4-5A Bolt

4 MS20004-6 Bolt

24 MS24694-S99 Screw

3 MS27039-1-21 Screw

1 MS29512-12 Packing

1 MS29513-114 Packing

1 MS29513-226 Packing

1 MS29513-230 Packing

1 MS29513-270 Packing

3 NAS1149D0332J Washer

9 NAS1149D0416J Washer

2 NAS1189-3P6 Screw

3 NAS43DD3-51N Spacer

4 NAS6204-6 Bolt

AR 299-947-066, Type I Adhesive (C-301)

1 412-961-503-102 Modification, Interior Auxiliary Fuel

1 70-061H000T060A Hose Assembly

1 AN4-10A Bolt

2 AN4-5A Bolt

2 AN5-4A Bolt

1 AN5-7A Bolt

2 AS21919WDG03Y Clamp

1 AS5174W0806 Union

3-26 Rev. 3 15 JUL 2020 Export Classification C, ECCN EAR99

BUY BELL PARTS, BUY BELL VALUE
 BHT-412-SI-91

QUANTITY PART NUMBER NOMENCLATURE

1 412-706-112-128 (Cont) Large Right Tank Kit, Consisting of:

1 MS35489-149 Grommet

1 NAS1149D0516J Washer

3 NAS1149F0463P Washer

3 NAS1149F0532P Washer

1 NAS6205-1 Bolt

AR A-A-59826, Type II, Thread

Class A, Size E

1 BHT-412-SI-91 Service Instruction

Export Classification C, ECCN EAR99 15 JUL 2020 Rev. 3 3-27/3-28

FOR BEST VALUE, BUY GENUINE BELL PARTS