CONTINENTAL MOTORS® AIRCRAFT ENGINE CATEGORY 3

SERVICE BULLETIN SB96-7D

Su pe rse de s S B96-7C
Compliance Will Enhance Safety TE CHN ICA L P O RTI O NS
FAA APPROVED
SUBJECT: Torque Limits
PURPOSE: To provide torque specifications for fasteners utilized on all CMI aviation
gasoline (AvGas) engines.
COMPLIANCE: During all maintenance, repair, or overhaul events.
MODELS
AFFECTED: All CMI aviation gasoline (AvGas) engines.

I. General Information
The torque specifications included in Service Document (SB96-7D) must be used for their
specific application. If an application is not listed under Section V, “Component Specific Torque
Specifications” (see Table 2, through Table 4), use the general torque specifications listed under
Section VI, “General Torque Specifications” (see Table 5 through Table 8). Refer to the
appropriate manufacturer’s overhaul instructions for aircraft or engine accessory torque
specifications.
WARNING
USE ONLY CLEAN 50 WEIGHT AVIATION ENGINE OIL APPLIED
ON SURFACES LISTED, UNLESS OTHERWISE SPECIFIED.
Do not apply any form of sealant to the crankcase cylinder deck, cylinder deck
chamfer, cylinder mounting flange, cylinder base O-ring, cylinder fastener
threads, or crankcase main bearing bosses. The use of RTV, silicone, Gasket
Maker or any other sealant on the areas listed above during engine assembly
will cause a loss of cylinder deck stud or through-bolt torque. Subsequent loss
of cylinder attachment load, loss of main bearing crush and/or fretting of the
crankcase parting surfaces will occur. The result will be cylinder separation
from the crankcase, main bearing movement, oil starvation, and catastrophic
engine failure.
Table 1. Table of Contents
Torque Specifications Page
Table 2. Component Specific Torque Specifications 4
Table 3. Specific Torque for Non-Lubricated Hardware 11
Table 4. FADEC Components (Non-Lubricated Hardware) 11
Table 5. General Torque Specification  12
(for bolts, nuts, screws, driving studs, and pipe plugs)
Table 6. Hydraulic Line Torque Specification 12
Table 7. Straight Thread Fitting Torque Specification 13
Table 8. Hose Fitting (“B” Nut) Torque Specification 13

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©2015 Continental Motors, Inc.
II. Torque Guidelines
WARNING
Proper torquing practices cannot be over emphasized. Torque
procedures are provided to achieve correct preloading of
fasteners. If the fasteners are not properly plated, the fastener
threads are not clean and free of deformation or are not
properly lubricated, the correct fastener preload will not be
achieved even though the given torque value is reached. For
this reason, it is critical that all fasteners be inspected for
proper plating, thread form, and correctly lubricated prior to
torquing. Failure to verify a fastener's serviceability or to
correctly lubricate the fastener prior to assembly and torquing
will result in the fastener not being properly preloaded and
subsequent failure of the fastener may occur.
• Before torquing the hardware, verify the hardware size is correct.
• The accuracy of any torque indicating wrench depends on a smooth application of
force and current calibration traceable to the National Institute of Standards and
Technology, verifiable by the calibration data label affixed to the tool.
• If cotter pin holes must be aligned, set the torque wrench at the low limit and tighten
the nut to the first hole beyond this torque; do not exceed the maximum specified
torque limit. This torquing procedure must be followed for all applications requiring
cotter pin hole alignment.
• If a nut slot cannot be aligned with a cotter pin hole within the specified limits,
substitute another serviceable nut to attain alignment.
• If the cotter pin hole in a stud lies beyond the stud nut slots after the nut has been
torqued, verify if the issued hardware is correct for the installation and the stud is
correctly installed to the proper height.
• Check studs for necking damage (over stretch/misshapen deformity) due to excessively
applied torque.
• Check the part for reduced thickness resulting from wear or incorrect part.
• Where applicable, special instructions/details are provided in footnotes following each
table.
• The notation (AR) refers to “As Required” in all torque specification tables.

III. Cylinder Torque Procedures

Proper cylinder installation requires a multiple step torquing process. Lubricating, preloading
torque, and achieving final torque values (not to exceed torque limits). Refer to the applicable
Maintenance and/or Overhaul Manual for the proper torquing sequence.

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IV. Supersedures
1. Through bolt nuts P/N's 634505 and 649496 have been superseded by nut P/N 652541. At
engine overhaul, all P/N 634505 and 649496 flanged through bolt nuts must be replaced with
P/N 652541 (flanged 12 point nut).
NOTE: If replacing P/N 634505 or 649496 (less that a complete set, prior
to engine overhaul), torque the replacement nut P/N 652541 to the
required valve of the original fasteners (P/N 634505 or 649496).
a. Nut P/N 634505 is a flanged 6 point (hex) nut requiring a torque value of 690-710 inch
lbs.
b. Nut P/N 649496 is a flanged 6 point (hex) nut requiring a torque value of 790-810 inch
lbs.
c. Nut P/N 652541 is a flanged 12-point nut requiring a torque value of 790-810 inch lbs.
2. Connecting Rods
a. Nut, Connecting Rod (nut P/N 626140 w/bolt P/N 35972) is superseded by Nut,
Connecting Rod (Spiralock nut P/N 654487 w/bolt P/N 655960).
b. Nut, Connecting Rod (nuts 24804 or 626140 w/bolt P/N 530213) and Nut, Connecting
Rod (Spiralock nut P/N 654487 w/bolt P/N 654693) are superseded by Nut, Connecting
Rod (Spiralock nut P/N 654487 w/bolt P/N 655959).

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V. Component Specific Torque Specifications
Table 2. Component Specific Torque Specifications
Torque Value Models Affected (Non-standard, see
Size Fastener In-Lbs Ft-Lbs General Torque Specification)
CRANKCASE
.25-28 Nut, Crankcase Flange 100-125 8.3-10.4 A, C, & E Series, O-200, O-300, 
O-470 (AR), IO-240 & IOF-240
.25-28 Nut, Engine Mount Leg 90-100 7.5-8.3 C-125, C-145 & O-300
Bushing
.25-28 Nut, Tie Bolt Prop Shaft Cages 90-110 7.5-9.2 GO-300
.31-18 Bolt, Oil Sump Flange 155-175 12.9-14.6 IO-346, O-470, IO-470, TSIO-470, 
GTSIO-520, IO-520, L/TSIO-520, IO-550,
IOF-550, TSIO-550, TSIOF-550 & 
TSIOL-550
.31-24 Nut, Crankcase Flange 180-220 15.0-18.3 IO-346, O-470, IO-470, TSIO-470, 
GTSIO-520, IO-520, L/TSIO-520, IO-550,
IOF-550, TSIO-550, TSIOF-550 & 
TSIOL-550
.31-24 Nut, Crankcase Backbone 240-280 20.0-20-3 (AR) Stainless Steel Hardware Only
.31-24 Nut, Crankcase Through Bolts 180-220 15.0-18.3 O-470 (AR), & E Series
.31-24 Nut, Magneto to Crankcase 100-120 8.3-10.0 All Models (AR)
.31-24 Nut, Magneto Gearshaft 190-210 15-8-17.5 IO-360 & L/TSIO-360
Support to Crankcase,
ConeLok
.31-24 Nut, Self-Locking, Fuel Pump 155-175 12.9-14.6 O-200-A, B & D; O-300-A & D
Cover
.38-24 Bolt, Crankcase Through Bolts, 275-325 22.9-27.1 GO-300
Front Main Only
.38-24 Nut, Crankcase Through Bolts, 370-390 30.8-32.5 O-470 & E Series
Front
.38-24 Nut, Crankcase Through Bolts, 275-325 22.9-27.1 All 470, 520 & 550
Upper Rear
.38-24 Nut, Crankcase Through Studs 275-325 22.9-27.1 A Series, C-75, C-85, C-90 & O-200
.38-24 Nut, Crankcase Tie Bolts 370-390 30.8-32.5 All (AR) EXCEPT IO-240, IOF-240 & 360
.38-24 Nut, Crankcase Tie Bolts 275-325 22.9-27.1 All IO-240, IOF-240, & 360
.38-24 Nut, Cylinder to Crankcase 410-430 34.2-35.8 A, C, & E Series, O-200, O-300, GO-300 &
Stud O-470
.38-24 Nut, Cylinder to Crankcase 440-460 36.7-38.3 All IO-240, IOF-240, & 360
Studs
.38-24 Nut, Mounting Bracket to 275-325 22.9-27.1 All Models (AR)
Crankcase
.44-20 Nut, Crankcase Tie-Bolts-Nose 440-460 36.6-38.3 All Models (AR)
& Below Camshaft
.44-20 Nut, Cylinder to Crankcase 490-510 40.8-42.5 All Models EXCEPT TSIOL-550
Studs
.44-20 Nut, Cylinder to Crankcase 590-610 49.2-50.8 TSIOL-550
Studs
.44-20 Nut, Cylinder to Crankcase 400-450 33.3-37.5 A Series, C-75, C-85 & C-90
Through Studs

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 Table 2. Component Specific Torque Specifications
Torque Value Models Affected (Non-standard, see
Size Fastener In-Lbs Ft-Lbs General Torque Specification)
.44-20 Nut, Front & Rear Crankcase 490-510 40.8-42.5 O-200
Bearing Through Studs
.44-20 Nut, Through Bolt at Cadmium 440-460 36.6-38.3 All Models (AR)
Plated Washer
.44-20 Nut, Through Bolt at Cylinder 490-510 40.8-42.5 All (AR) EXCEPT IO-240, IOF-240, & 360
Flange
.44-20 Nut, Through Bolt at Cylinder 590-610 49.2-50.8 All IO-240, IOF-240, & 360
Flange
.44-20 Nut, Through Bolt at Front 490-510 40.8-42.5 All Models (AR)
Mount Belt-Driven Alternator
.44-20 Nut, Tie Bolts at Nose and 340-360 28.3-30.0 GO-300
Prop Shaft Cages
.50-20 Nut, Crankcase Through Bolt 615-635 51.2-52.9 IO-346, O-470, IO-470, TSIO-470, 
at Cadmium Plated Washer GTSIO-520, IO-520, L/TSIO-520, IO-550,
IOF-550, TSIO-550, & TSIOF-550
.50-20 Nut, Crankcase Through Bolt 690-710 57.5-59.2 All IO-346, All 470, All 520 & All 550 
at Cylinder Flange, P/N EXCEPT TSIOL-550
634505 (6 point/0.33” tall)
.50-20 Nut, Crankcase Through Bolt 790-810 65.8-67.5 All IO-346, All 470, All 520 & All 550 
at Cylinder Flange, P/N EXCEPT TSIOL-550
652541 (12 point)
.50-20 Nut, Crankcase Through Bolt 790-810 65.8-67.5 TSIOL-550
at Cylinder Flange, P/N
649496 (6 point/0.43” tall)
.50-20 Nut, Crankcase-Nose Tie Bolts 640-660 53.5-55.0 All Models (AR)
.50-20 Nut, Through Bolt at Cadmium 690-710 57.5-59.2 TSIOL-550
Plated Washer
.62-18 Plug, (using crush washer) 190-210 15.8-17.5 All Models (AR)
GEARS
.25-28 Bolt, Gear to Camshaft 140-160 11.7-13.3 A, C & E Series, O-200, O-300, O-470, 
IO-240, & IOF-240
.25-28 Bolt, Gear to Crankshaft  140-160 11.7-13.3 A, & C Series, O-200, O-300, GO-300, 
(P/N 22532)1 IO-240 & IOF-240
.25-28 Bolt, Gear to Crankshaft  170-175 14.2-14.6 E Series, O-470 Numerical, O-470-A & E
(P/N 534904)1
.31-24 Bolt, Gear to Camshaft 240-260 20.0-21.7 E Series, IO-360, L/TSIO-360, IO-346,
O-470, IO-470, TSIO-470, GTSIO-520, 
IO-520, L/TSIO-520, IO-550, IOF-550,
TSIO-550, TSIOF-550, & TSIOL-550
.31-24 Bolt, Gear to Crankshaft 240-260 20.0-21.7 E Series, IO-360, L/TSIO-360, IO-346
(Lower Hardness Identified
with Green Dykem)1
.31-24 Bolt, Gear to Crankshaft (Bolt 380-420 31.7-35.0 O-470, IO-470, TSIO-470, IO-520, 
Hardness RC 38-42)1 L/TSIO-520, IO-550, IOF-550, TSIO-550,
TSIOF-550, & TSIOL-550

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 Table 2. Component Specific Torque Specifications
Torque Value Models Affected (Non-standard, see
Size Fastener In-Lbs Ft-Lbs General Torque Specification)
.31-24 Bolt, Face Gear to Camshaft 140-150 11.7-12.5 IO-346, GTSIO-520, IO-520, TSIO-520
(AR), IO-550, IOF-550, TSIO-550, &
TSIOL-550
.31-24 Nut, Generator or Alternator 175-200 14.6-16.7 A, C & E Series, O-200, O-300, GO-300,
Gear IO-360, & L/TSIO-360
.31-24 Nut, Generator Gear (531231) 175-195 14.6-16.3 E Series
w/washer (401507)
.38-24 Bolt, Vacuum & Fuel Pump 275-325 22.9-27.1 IO-240 & IOF-240
Gear to Camshaft
.38-24 Nut, Slick Mag Gear to 120-180 10.0-15.0 O-200 & O-300
Magneto Shaft
CONNECTING RODS
.38-24 Nut, Connecting Rod  400-475 33.3-39.6 A & C Series, O-200, O-240, IO-240, 
(nuts 24804 or 626140  IOF-240, O-300, GO-300, IO-360 & 
w/bolt P/N 530213)2, 3, 4 L/TSIO-360
.38-24 Nut, Connecting Rod  400-475 33.3-39.6 E-Series O-470, IO-470, with 654796
(Spiralock nut P/N 654487 Connecting Rod
w/bolt P/N 655960)
.38-24 Nut, Connecting Rod  400-475 33.3-39.6 E-185, E-205, E-225, IO-346, O-470
(nut P/N 626140 w/bolt P/N Numbered and Lettered Engines IO-470,
35972)2, 3, 5 TSIO-470, with 628751 Connecting Rod
.38-24 Nut, Connecting Rod 490-510 40.8-42.5 O-200, O-240, IO-240, IOF-240, O-300,
(Spiralock nut P/N 654487  IO-360, L/TSIO-360, O-470, IO-470, 
w/bolt P/N 654693)5 TSIO-470
.38-24 Nut, Connecting Rod 490-510 40.8-42.5 O-200, O-240, IO-240, IOF-240, O-300,
(Spiralock nut P/N 654487  IO-360, L/TSIO-360, O-470, IO-470, 
w/bolt P/N 655959) TSIO-470
.44-20 Nut, Connecting Rod 550-600 45.8-50.0 O-470, IO-470, IO-520, L/TSIO-520-AE &
(Spiralock nut P/N 643215  CE, IO-550, IOF-550, TSIO-550, 
w/bolt P/N 643112) TSIOF-550 & TSIOL-550
.44-20 Nut, Connecting Rod 690-710 57.5-59.2 O-470, IO-470, GTSIO-520, IO-520, 
(Spiralock nut P/N 654490  L/TSIO-520, IO-550, IOF-550, TSIO-550,
w/bolts P/N 643112 or P/N TSIOF-550 & TSIOL-550
655958)
.44-28 Nut, Connecting Rod 475-525 39.6-43.8 IO-346, O-470, IO-470, TSIO-470, IO-520
(rod P/N 646476 w/bolts & TSIO-520 (EXCEPT L/TSIO-520-AE &
P/N 629340 and nut 628109)2 CE)
.44-28 Nut, Connecting Rod 550-575 45.8-47.9 GTSIO-520
(rod P/N 646474 w/bolts
P/N 631794 and nut 631554) 2
MISCELLANEOUS FUEL INJECTION
#8-32 Screw, Aneroid Body Hold 17.5-22.5 1.5-1.9 All Fuel Injected Model (AR)
Down (AN500-8-14)
#8-32 Screw, Manifold Cover Hold 22-26 1.8-2.2 All Fuel Injected Model (AR)
Down (AN503-8-12)
.125-27 Fitting, Cover, Fuel Pump, 60-80 5.0-6.7 All Fuel Injected Model (AR)
Vapor Separator

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 Table 2. Component Specific Torque Specifications
Torque Value Models Affected (Non-standard, see
Size Fastener In-Lbs Ft-Lbs General Torque Specification)
.125-27 Nozzle, Fuel Injector  55-65 4.6-5.4 All Fuel Injected Model (AR)
(w/anti-seize compound)
.19-24 Through Bolt, Fuel Pump 29-31 2.4-2.6 All Fuel Injected Model (AR)
.25-28 Ejector, Cover, Fuel Pump, 90-100 7.5-8.3 All Fuel Injected Model (AR)
Vapor Separator
.25-48 Jam Nut, Aneroid Stem 25-30 2.1-2.5 All Fuel Injected Model (AR)
Adjustment
.31-24 Nozzle, Fuel Injector  55-65 4.6-5.4 All Fuel Injected Model (AR)
(w/anti-seize compound)
.31-24 Nut, Throttle and Mixture 100-120 8.3-10.0 All Fuel Injected Model (AR)
Control Levers to Shaft
.31-32 Nut, Fuel Injection Line 40-45 3.3-3.7 All Fuel Injected Model (AR)
.38-24 Nut, Fuel Injection Line 55-60 4.6-5.0 All Fuel Injected Model (AR)
.50-24 Nut, Air Reference Sleeve “B” -- -- All Turbocharged Models
Nut to Air Reference Line6
.62-18 Metering Unit Plug & Screen 120-130 10.0-10.8 All Fuel Injected Model (AR)
Assembly (w/new gasket)

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 Table 2. Component Specific Torque Specifications
Torque Value Models Affected (Non-standard, see
Size Fastener In-Lbs Ft-Lbs General Torque Specification)
MISCELLANEOUS LUBRICATION SYSTEM FASTENERS
.25-20 Bolt, Oil Cooler to Adapter 100-110 8.3-9.2 IO-360, L/TSIO-360, O-470,
IO-470,TSIO-470, IO-520, TSIO-520 (AR),
IO-550, IOF-550, TSIO-550, 
TSIOF-550 & TSIOL-550
.25-20 Bolt, Oil Pump Cover to 75-85 6.3-7.1 All Models (AR)
Crankcase
.25-28 Nut, Collar Assembly - 75-85 6.3-7.1 O-470, IO-470,TSIO-470, IO-520,
Governor Oil Transfer TSIO-520 (AR), IO-550, IOF-550,
TSIO-550, TSIOF-550 & TSIOL-550
.375-18 Oil Cooler Cross Fitting7 185 min. 15.4 min. TSIO-550-C, K, N; TSIOF-550-D, K
.38-24 Tachometer, Shaft to Oil Pump 280-300 23.3-25.0 IO-360-D, L/TSIO-360
Drive Gear
.62-18 Plug, Bypass Valve 190-210 15.8-17.5 O-200-D
.62-18 Plug, Oil Cooler  190-210 15.8-17.5 All Models (AR)
(w/crush washer)
.62-18 Plug, Oil Suction Tube  190-210 15.8-17.5 All Models (AR)
(w/crush washer)
.62-18 Plug, Oil Sump Drain 190-210 15.8-17.5 All Models (AR)
.62-18 Oil Filter Cartridge 180-216 15.0-18.0 All Models (AR)
.75-16 Oil Filter, Disposable 192-216 16.0-18.0 All Models (AR)
.75-16 Plug, Oil Sump Drain 190-210 15.8-17.5 IO-470-M & IO-520-E
.88-16 Cap, Oil Relief Valve 190-210 15.8-17.5 O-200, IO-240, IOF-240, O-300 & 
L/TSIO-360
.88-16 Plug, Oil Bypass 240-260 20.0-21.7 O-470, IO-470,TSIO-470,IO-520, 
TSIO-520, GTSIO-520, IO-550, IOF-550,
TSIO-550, TSIOF-550 & TSIOL-550
1.00-14 Vernatherm, Oil Temperature 190-210 15.8-17.5 All Models (AR)
Control Valve8
1.00-18 Screen Assembly, Scavenge 200-210 16.7-17.5 O-300 (AR), IO-360 (AR), L/TSIO-360 (AR)
Oil
1.12-18 Housing, Oil Pressure Relief 240-260 20.0-21.7 IO-346, O-470, IO-470,TSIO-470,IO-520,
Valve (New Gasket) TSIO-520, GTSIO-520, IO-550, IOF-550,
TSIO-550, TSIOF-550 & TSIOL-550
1.25-18 Plug, Special Vernatherm 310-320 20.8-29.2 All Models (AR)
1.25-18 Vernatherm, Oil Temperature 410-420 34.2-35.0 All Models (AR)
Control Valve
1.375-16 LH Housing, Tachometer Drive 250-350 20.8-29.2 All Models (AR)
1.75-16 Oil Filter Adapter Lock Nut 500-520 41.6-43.3 O-300 (AR), IO-360 (AR) & L/TSIO-360
(AR)
1.75-16 Oil Filter Screen (w/new crush 500-520 41.6-43.3 All Models (AR)
gasket. Install gasket w/parting
line against screen face.)

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 Table 2. Component Specific Torque Specifications
Torque Value Models Affected (Non-standard, see
Size Fastener In-Lbs Ft-Lbs General Torque Specification)
MISCELLANEOUS CYLINDER HARDWARE
.071 (18mm) Spark Plug 9 300-360 25.0-30.0 All Models (AR)
.125-27 Connector, Cylinder Drain 60-80 5.0-6.7 All Models (AR)
.19-32 Screw, Cylinder Baffle to Baffle -- -- All Models (AR)
Support10
.19-32 Screw, Cylinder Baffle to Baffle 36-50 3.0-4.2 All Models (AR)
Base
.25-20 Bolt, Rocker Shaft Hold Down 85-110 7.1-9.2 O-470-2, 4, 13, 13A & O-470-B (AR)
.25-20 Bolt, Through Bolted Rocker 90-100 7.5-8.3 O-470, IO-470, TSIO-470, IO-520, 
Shaft TSIO-520 (EXCEPT BE), IO-550 (EXCEPT
G, N, P & R), IOF-550 (EXCEPT N, P & R)
& TSIOL-550
.25-20 Screw, Rocker Box Cover 55-65 4.6-5.4 IO-240, IOF-240, IO-360 & L/TSIO-360
(tighten two lower screws first)
.25-20 Screw, Rocker Cover 55-65 4.6-5.4 All Models (EXCEPT 240 & 360)
.25-20 Screw, Intake Flange 85-110 7.1-9.2 All Models (AR)
.25-20 Set Screw, Rocker Shaft, 45-55 3.8-4.6 O-200, O-300
Locking
.25-28 Nut, Rocker Shaft Hold Down 110-120 9.2-10.0 IO-240, IOF-240 & All 360
.25-28 Nut, Exhaust (self locking) 120-130 10.0-10.8 All Models (AR)
.25-28 Nut, Exhaust Manifold Flange 100-110 8.3-9.2 All Models (AR)
(spirotallic gasket)
.31-18 Bolt, Rocker Shaft Hold 190-210 15.8-17.5 GTSIO-520, TSIO-520-BE, IO-550-G, N, P
Down11 & R, IOF-550-N, P & R, TSIO-550 &
TSIOF-550
.31-24 Bolt, Rocker Shaft Hold 85-110 7.1-9.2 O-470, IO-470, TSIO-470, IO-520, 
Down12 TSIO-520 (EXCEPT BE), IO-550 (EXCEPT
G, N, P & R), IOF-550 (EXCEPT N, P & R)
& TSIOL-550
.31-24 Nut, Exhaust Manifold Flange 200-210 16.7-17.5 All Models (AR)
(spirotallic gasket)
.31-24 Nut, Induction Tube Flange 50-70 4.2-5.8 IO-240, IOF-240 & All 360
.44-20 Plug, Cylinder Drain  50-70 4.2-5.8 TSIOL-550
(w/O-ring)
MISCELLANEOUS FASTENERS
.19-32 Nut, Carburetor Air Intake Box 9-10 0.75-0.83 O-200-D
Control Lever
.25-62 Clamp, Hose, Oil Gauge Rod 12-16 0.3-1.3 IO-360 & L/TSIO-360 (AR)
.25-62 Clamp, Hose, Magneto 10-14 0.8-1.17 All Models with Pressurized Magnetos
Pressurization
.25-28 Nut, Exhaust Coupling,  42 3.5 TSIO-520-L, LB & WB
“V” band clamp13
.31-18 Bracket, Turbocharger 220-250 18.3-20.8 GTSIO-520-F, K
.31-18 Bolt, Alternator Mounting 150-180 12.5-15.0 IO-346, All 520 & All 550

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 Table 2. Component Specific Torque Specifications
Torque Value Models Affected (Non-standard, see
Size Fastener In-Lbs Ft-Lbs General Torque Specification)
.38-16 Bolt, Turbocharger to Bracket 310-350 25.8-29.2 TSIO-520-L1, LB, UB, WB
.38-24 Nut, Slick Mag Impulse 128-180 10.0-15.0 All Model using Slick Impulse Coupled
Coupling to Magneto Shaft Magnetos
.38-24 Nut, Starter to Adapter 200-220 16.7-18.3 O-300 (AR), GO-300 (AR), IO-346, 
All 470, 520 & 550
.44-20 Nut, Alternator Sheave to 600-720 50-60 TSIO-520-B
Starter Shaft
.56-18 Nut, Starter Shaft Gear14 450-500 37.5-41.6 IO-520, IO-550, IOF-550,TSIO-550,
TSIOF-550
.56-18 Nut, Starter Jaw, Crankshaft 575-625 47.9-52.1 O-470-Numeral
.56-18 Nut, Generator Pulley Drive 450-500 37.5-41.7 IO-346, ALL 470, IO-520, TSIO-520, 
IO-550, IOF-550, TSIO-550, TSIOF-550 &
TSIOL-550
.56-24 Screw, Shoulder,  800-850 66.6-70.8 TSIO-520-BE, TSIO-550, TSIOF-550
Air Conditioning Idler Sheave
.62-32 Nut, Alternator Hub Assembly 300-450 25.0-37.5 IO-346, IO-520(AR), TSIO-520 (AR),
GTSIO-520 (AR), IO-550, IOF-550, 
TSIO-550, TSIOF-550 & TSIOL-550
.66-20 Nut, Alternator or Generator 450-500 37.5-41.7 O-470, IO-470, IO-520 (AR), TSIO-520
Pulley (AR), TIARA (AR), IO-550, IOF-550, 
TSIO-550, TSIOF-550 & TSIOL-550
.75-16 Nut, Starter Shaft Gear, --- 180-220 GTSIO-520
Viscous Damper
.88-18 Adapter, Tachometer 120-180 10.0-15.0 IO-240, IOF-240 & All 360
Reduction Gear
1. Heat crankshaft gear to 300º F; install gear on crankshaft immediately for shrink fit. Ensure the gear seats tightly against the end of the
crankshaft by tapping lightly with a brass hammer.
2. Torque to low limit. If cotter pin will not align with holes, increase torque gradually, up to high limit only. If cotter pin holes will not align
within torque range, replace the nut and repeat. In no case shall nuts be tightened below the minimum or above the maximum torque
limit. Refer to the most current revision of CMI Service Document SIL93-15 for special cotter pin installation instructions in 360 series
engine connecting rods.
3. A) P/N 530184 connecting rod (identified by forging number 530186), P/N A35159 (identified by forging 5561) and P/N A35160 (also
identified by forging number 5561) must be assembled with P/N 530213 bolt, P/N 24804 or 626140 nut and P/N 639292 cotter pin. 
B) Assemble P/N A36121 connecting rods utilizing the P/N 632041 forging with the part numbers indicated in current technical data.
Assemble P/N A36121 connecting rod assemblies utilizing the P/N 40742 forging with P/N 35972 connecting rod bolt, P/N 24804 nut and
P/N MS24665-132 cotter pin.
4. Bolt P/N superseded by 655960. Do not mix with obsolete parts.
5. Bolt P/N superseded by 655959. Do not mix with obsolete parts.
6. Snug nut finger tight to set seal between nut and male connector, then tighten additional 3/4 to 1 turn.
7. Install fitting hand-tight. Wrench tighten the cross fitting to the appropriate clocking of fitting within 1-3 turns from the finger tight position.
Minimum torque of 185 in/lbs must be achieved upon clocking position of fitting. The fitting is not to be loosened in order to achieve
proper alignment (clocking).
8. Apply Loctite Pipe Sealant 592.
9. Lubricate spark plug threads with spark plug manufacturer’s recommended lubricant.
10. Install baffle screw until seated against flat washer; then, tighten an additional 2-6 turns. Baffle to be snug but not distorted. Verify mini-
mum one (1) thread protrudes past nut plate on lower cylinder baffle.
11. Do not realign hex cap screw to mate with tab washer.
12. Must be reworked to through bolt rocker shaft configuration according to most current revision of CMI Service Document M92-6.
13. Strike outer periphery of coupling band lightly to distribute load. Tighten to 50-60 in/lb. for P/N 641284 clamp and 60-70 in/lb. for P/N
653832 clamp.
14. Align and adjust compressor belt tension according to most current revision of CMI Service Document M89-6.

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 Table 3. Specific Torque for Non-Lubricated Hardware
Torque Value
Size Fastener In-lbs Ft-lbs Models Affected
--- Clamp, Hose 25-35 2.0-2.9 All Models (AR)
#8-32 Screw, Throttle Lever 17.5-22.5 1.5-1.9 All Models (AR)
#10-32 Nut, Magneto Ground Terminal 15-17 1.25-1.41 CMI S-20/200, S-1200
Magnetos
#10-32 Nut, Magneto Ground Terminal 13-15 1.08-1.25 Slick Magnetos
#10-32 Screw, Ignition Harness Cable Outlet Plate 12-15 1.0-1.25 CMI S-20/200 Magnetos
Various Nut, Ignition Harness Cable Outlet Plate 18-22 1.5-1.8 CMI S-1200 Magnetos
Various Screw, Ignition Harness Cable Outlet Plate 18-28 1.5-2.33 Slick Magnetos
.125-27 Fuel Injector Nozzle to Cylinder1 55-65 4.6-5.4 All Fuel Injection Models
.31-24 Nut, Cable Attach 55-60 4.6-5.0 All w/Energizer Starter
.31-32 B-Nut, Fuel Injection Line to Fuel Injector Nozzle 40-45 3.3-3.8 All Models (AR)
.375-24 B-Nut, Fuel Injection Line to Fuel Manifold Valve 55-60 4.6-5.0 All Non-FADEC Fuel
Injected
.56-24 Sensor, Magneto (Tachometer) 35-40 2.9-3.3 All Models (AR)
.625-24 B-Nut, Ignition Lead to Spark Plug 90-95 7.5-7.91 All Non-FADEC
.68-24 Sensor, Magneto (Tachometer) 35-40 2.9-3.3 All Models (AR)
.75-20 B-Nut, Ignition Lead to Spark Plug 110-120 9.2-10.0 All Non-FADEC
1.12-18 Oil Pressure Relief Valve Housing 240-260 20.0-21.7 All Models (AR)
1. Apply CMI P/N 646943 Anti-Seize Lubricant

Table 4. FADEC Components (Non-Lubricated Hardware)

Torque Value
Size Fastener In-lbs Ft-lbs Models Affected
#4 Screw, ECU 50-Pin Connector 10-15 0.83-1.25 All FADEC
#4 Screw, Speed Sensor 25-Pin Connector 10-15 0.83-1.25 All FADEC
#10 Bolt, Ground Strap 25-35 2.02.9 All FADEC
.125-27 Adapter Fitting, Manifold Air Temperature 60-80 5.0-6.6 All FADEC
.25-18 NPT Sensor, Fuel Pressure 130-150 10.83-12.5 All FADEC
.25-18 NPT Sensor, Manifold Pressure 130-150 10.83-12.5 All FADEC
.25-24 Bolt, ECU Mount 60-70 5.0-5.83 All FADEC
.25-.62 Clamp, Exhaust Gas Temperature Sensor 30-35 2.5-2.9 All FADEC
.31-32 Nut, Fuel Injection Solenoid Retaining 24-28 2.0-2.3 All FADEC
.375-24 Bayonet Adapter, Cylinder Head Temp. Sensor 55-65 4.58-5.41 All FADEC
.375-24 Fuel Injection Line to Fuel Distribution Block 55-60 4.6-5.0 All FADEC
.437-24 Compression Fitting, Manifold Air Temp. Ferrule 145-155 12-12.9 All FADEC
.75-20 B-Nut, Ignition Harness to Spark Tower 110-120 9.1-10.0 All FADEC
.75-20 Jam Nut, ECU Spark Tower 110-120 9.1-10.0 All FADEC

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VI. General Torque Specifications
Table 5. General Torque Specification
Bolts, Nuts, Screws
Torque
Size In. lbs. Ft. lbs.
#2-56 1.4-2.6 N/A
#4-40 2.9-5.5 N/A
#6-32 5.3-10.1 N/A
#8-32 17.5-22.5 1.5-1.9
#10-32 36-50 3.0-4.2
#10-24 21-25 1.7-2.0
.250-20 75-85 6.3-7.1
.250-28 90-100 7.5-8.3
.3125-18 155-175 12.9-14.6
.3125-24 180-220 15.0-18.3
.375-16 220-260 18.3-21.7
.375-24 275-325 22.9-27.1
.44-20 400-450 33.3-37.5
.50-20 550-600 45.8-50.0
Driving Studs
.250-20 50-70 4.2-5.8
.3125-18 100-150 8.3-12.5
.375-16 200-275 16.7-22.9
.44-14 300-425 25.0-35.4
Pipe Plugs
.062-27 30-40 2.5-3.3
.125-27 60-80 5.0-6.7
.250-18 130-150 10.8-12.5
.375-18 185-215 15.4-18.0
.500-14 255-285 21.3-23.8
.750-14 310-350 25.8-29.2

Table 6. Hydraulic Line Torque Specification

Hose Size Hose End Fitting Material Torque (In-lbs. Models
.44-20 Nut-Self-Locking #4 hose 115-165 TSIO-520-L, LB, WB
.56-18 Nut-Self-Locking #6 hose 185-335 TSIO-520-L, LB, WB
.75-16 Nut-Self-Locking #8 hose 360-570 TSIO-520-L, LB, WB

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 NOTE: Fitting torques in Table 7 are for reference only. For all
tapered (NPT/NPTF) fittings that must be oriented to a specific
angle (clocked) for mating with another fitting or hose, screw the
fitting into the port finger-tight. Wrench tighten additional 2-3 turns
until the fitting is oriented at the desired angle. Do not loosen the
fitting to achieve proper alignment.
Table 7. Straight Thread Fitting Torque Specification
Size Fitting Size Torque (In-lbs)
.31-24 Brass / Aluminum 15-30
.31-24 Steel 15-50
.38-24 Brass / Aluminum 40-65
.38-24 Steel 50-90
.44-20 Brass / Aluminum 60-80
.44-20 Steel 70-120
.44-24 Steel 60-80
.56-18 Brass / Aluminum 75-125
.56-18 Steel 90-150
.75-16 Brass / Aluminum 150-250
.75-16 Steel 135-250
.88-14 Brass / Aluminum 200-350
.88-14 Steel 300-400

Table 8. Hose Fitting (“B” Nut) Torque Specification

Hose Size Hose End Fitting Material Torque (In-lbs)
-2 (.31-24) Brass/Aluminum Fitting 50-80
-2 (.31-24) Steel Fitting 75-120
-3 (.38-24) Brass/Aluminum Fitting 70-105
-3 (.38-24) Steel Fitting 95-140
-4 (.4375-20) Brass/Aluminum Fitting 100-140
-4 (.4375-20) Steel Fitting 135-190
-5 (.500-20) Brass/Aluminum Fitting 130-180
-5 (.500-20) Steel Fitting 170-240
-6 (.5625-18) Brass/Aluminum Fitting 150-195
-6 (.5625-18) Steel Fitting 215-280
-8 (.750-16) Brass/Aluminum Fitting 270-350
-8 (.750-16) Steel Fitting 470-550
-10 (.875-14) Brass/Aluminum Fitting 360-430
-10 (.875-14) Steel Fitting 620-745
-12 (1.063-12) Brass/Aluminum Fitting 460-550
-12 (1.063-12) Steel Fitting 855-1055

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