Time Between Overhaul Periods (TBO) - 33580M

1. PLANNING INFORMATION

A. Effectivity

Owners and Operators of Aircraft Using Woodward Propeller Governors, Pumps,

Auto Feather Valves, and Speed Signal Generators.

Aircraft Service Facilities and Certificated Governor Repair Stations.

Airframe Manufacturers.

B. Concurrent Requirements

None.

C. Reason

To provide Recommended Time Between Overhaul Periods (TBO) for Woodward Propeller
Governors, Pumps, Auto Feather Valves, and Speed Signal Generators.

D. Description

Wear rates of governor assemblies and accessories will vary with operating conditions.
The listed TBOs are based on the following assumptions:

1. Continuous operation with a minimum of 10 hours per month.

2. Engine maintenance performed as specified by the engine and airframe manufacturers.

3. The unit has not been subjected to sudden stoppage, lightning strike, or oil
contamination (Overhaul is required at any time the unit is subjected to sudden
stoppage, lightning strike, or contaminated oil.).

Exceptions to specified TBO:

1. Aircraft engaged in crop dusting or other chemical application flying should reduce the unit
TBO to match the percent of reduction in the recommended engine TBO.

Issued Jan 01/1982 TBO S/B-33580-M

Revision 12: Feb 28/2007 Page 1 of 12
 2. The recommended calendar time limit is 6 years for units not in continuous service
with a minimum of 120 hours per year. For units in continuous service with a minimum
of 120 hours per year, the unit can be operated to the recommended TBO in hours
provided the following inspections and conditions are met.

A. All Airworthiness Directives, Service Bulletins and Service Letters

have been complied with.

B. Unit is free from oil leaks.

C. Unit has no visible physical damage which would include cracks, corrosion, etc.

D. There has been no malfunction in the operation of the unit.

E. There has been no 6 month period when the unit was not operated
for a minimum of 10 hours.

3. Governors and accessories listed below might exceed the Woodward recommended Time
Between Overhaul (TBO) if they are maintained in accordance with an "On Condition"
or "Condition Monitored" system approved by the U.S. Federal Aviation Administration
or the Canadian Department of Transportation. These federally approved maintenance
monitoring methods become an alternate to the manufacturer’s recommended Time
Between Overhaul. When such governors are returned for servicing on an Investigate
and Repair As Necessary (IRAN) basis the customer must specify the Time Since New
(TSN) or Time Since Overhaul (TSO). Cooperating with the above approved maintenance
methods causes Woodward to "return to service" IRAN governors with accrued hours
in excess of Woodward’s recommended Time Between Overhaul.

E. Compliance

Not applicable.

F. Approval

Technical aspects of this service bulletin are FAA approved.

G. Manpower

No additional man hours required if accomplished during routine assembly/disassembly.

H. Weight and Balance

Not affected.

Issued Jan 01/1982 TBO S/B-33580-M

Revision 12: Feb 28/2007 Page 2 of 12
 I. Electrical Load Data

Not affected.

J. Software Accomplishment Summary

Not applicable.

K. References

None.

L. Other Publications Affected

None.

M. Interchangeability or Intermixability of Parts

Not applicable.

2. MATERIAL INFORMATION

A. Material - Price and Availability

For parts required at overhaul and pricing information please contact:

Woodward Aircraft Engine Systems
One Woodward Way
P.O. Box 405
Rockton, IL 61072-0405
USA
Telephone: (815) 624-1819
Facsimile: (815) 624-1926
----------OR----------
Woodward Aircraft Engine Systems
5 Shawfarm Road
Prestwick, Ayrshire KA9 2TR
SCOTLAND, UK
Telephone: 44-1292-677631
Facsimile: 44-1292-474231

B. Industry Support Information

None.

Issued Jan 01/1982 TBO S/B-33580-M

Revision 12: Feb 28/2007 Page 3 of 12
 C. Material Necessary for Each Aircraft/Engine/Component

See Material - Price and Availability

D. Material Necessary for Each Spare

Not applicable.

E. Reidentified Parts

Not applicable.

F. Tooling - Price and Availability

Not applicable.

3. RECOMMENDATIONS

(1) Recommended Time Between Overhaul (TBO) for Woodward Propeller Governors,
Pumps, Auto Feather Valves, and Speed Signal Generators are the same as
recommended TBO of engine on which unit is installed except for units listed
in the applicable Time Between Overhaul Table.

Reciprocating Engine Governor Time Between Overhaul Table

Governor TBO
210582 500 Hours
210692 500 Hours
210920 500 Hours
210921 500 Hours

Turboprop Primary Governor Time Between Overhaul Table

Governor TBO
A210765 2000 Hours
210492 3500 Hours
210508 3500 Hours
210527 3500 Hours
210528 3500 Hours

Issued Jan 01/1982 TBO S/B-33580-M

Revision 12: Feb 28/2007 Page 4 of 12
 Turboprop Primary Governor Time Between Overhaul Table (Continued)

Governor TBO
210537 3500 Hours
210538 3500 Hours
210540 3500 Hours
210541 3500 Hours
210542 3500 Hours
210558 3500 Hours
210560 3500 Hours
210561 3500 Hours
210563 3500 Hours
210564 3500 Hours
210570 3500 Hours
210581 3500 Hours
210600 3500 Hours
210735 3500 Hours
210736 3500 Hours
210737 3500 Hours
210738 3500 Hours
210739 3500 Hours
210741 3500 Hours
210742 3500 Hours
210743 3500 Hours
210744 3500 Hours
210746 3500 Hours
210749 3500 Hours
210939 3500 Hours
210940 3500 Hours
8210-100 3500 Hours
8210-101 3500 Hours
8210-103 2000 Hours
8210-104 3500 Hours

Issued Jan 01/1982 TBO S/B-33580-M

Revision 12: Feb 28/2007 Page 5 of 12
 Turboprop Primary Governor Time Between Overhaul Table (Continued)

Governor TBO
8210-108 3500 Hours
8210-109 3500 Hours
8210-110 3500 Hours
8210-112 3500 Hours
8210-115 3500 Hours
8210-121 6500 Hours
8210-260 3500 Hours
8210-261 3500 Hours
8210-262 3500 Hours
8210-263 3500 Hours
8210-264 3500 Hours
8210-265 2000 Hours
8210-300 2000 Hours

Turboprop Reversing Type Primary Governor Time Between Overhaul Table

Governor TBO
210544 3500 Hours
210547 3500 Hours
210549 3500 Hours
210557 3500 Hours
210559 3500 Hours
210566 3500 Hours
210567 3500 Hours
210568 3500 Hours
210569 3500 Hours
210574 4000 Hours
210575 4000 Hours
210576 4000 Hours
210577 3500 Hours

Issued Jan 01/1982 TBO S/B-33580-M

Revision 12: Feb 28/2007 Page 6 of 12
 Turboprop Reversing Type Primary Governor Time Between Overhaul Table (Continued)

Governor TBO
210578 4000 Hours
210589 4000 Hours
210599 4000 Hours
210935 4000 Hours
Except those manufactured or factory remanufactured prior to February 1973 - TBO 2200 Hours

Turboprop Propeller Governor with Pneumatic Overspeed Limiter (Airbleed Gover-

nor) Time Between Overhaul Table

Governor TBO
8210-002 4500 Hours
8210-003 4500 Hours
8210-004 4500 Hours
8210-006 4500 Hours
8210-007 4500 Hours
8210-008 2000 Hours
8210-009 2000 Hours
8210-018 2000 Hours
8210-020 2000 Hours
8210-021 2000 Hours
8210-024 4500 Hours
8210-025 4500 Hours
8210-027 4500 Hours
8210-029 4500 Hours
8210-033 2000 Hours
8210-034 4500 Hours
8210-035 4500 Hours
8210-037 4500 Hours
8210-041 ("A" Change or later) 3500 Hours
8210-042 (Prior to "A" change) 2000 Hours
8210-042 ("A" Change or later) 3500 Hours

Issued Jan 01/1982 TBO S/B-33580-M

Revision 12: Feb 28/2007 Page 7 of 12
 Turboprop Propeller Governor with Pneumatic Overspeed Limiter (Airbleed Governor)
Time Between Overhaul Table (Continued)

Governor TBO
8210-043 ("A" Change or later) 3500 Hours
8210-046 4500 Hours
8210-051 2500 Hours
8210-052 2500 Hours
8210-053 2500 Hours
8210-054 2500 Hours
8210-124 4500 Hours
8210-133 4500 Hours
8210-134 4500 Hours
8210-135 4500 Hours
8210-137 2500 Hours
8210-140 2000 Hours
8210-187 2500 Hours
8210-188 2500 Hours
8210-189 2500 Hours
8210-190 2500 Hours
8210-191 2500 Hours
8210-192 2500 Hours
8210-198 2500 Hours
8210-199 2500 Hours
8210-209 4500 Hours
8210-212 4500 Hours
8210-310 4500 Hours
8210-388 2500 Hours
8210-389 2500 Hours
8210-391 2500 Hours
8210-392 2500 Hours
8210-393 2500 Hours
8210-398 2500 Hours

Issued Jan 01/1982 TBO S/B-33580-M

Revision 12: Feb 28/2007 Page 8 of 12
 Turboprop Propeller Governor with Pneumatic Overspeed Limiter (Airbleed Governor)
Time Between Overhaul Table (Continued)

Governor TBO
8210-399 2500 Hours
8210-400 2500 Hours
8210-401 2500 Hours
8210-402 2500 Hours
8210-403 2500 Hours
8210-404 2500 Hours
8210-406 2500 Hours
8210-407 2500 Hours
8210-408 2500 Hours
8210-409 2500 Hours
8210-410 2500 Hours
8210-411 2500 Hours

Turboprop Overspeed Governor Time Between Overhaul Table

Governor TBO
210507 6500 Hours
210509 6500 Hours
210510 6500 Hours
210536 6500 Hours
210588 6500 Hours
210590 6500 Hours
210598 6500 Hours
210610 6500 Hours
210612 6500 Hours
210613 6500 Hours
210614 6500 Hours
210615 6500 Hours
210616 6500 Hours
210618 3500 Hours

Issued Jan 01/1982 TBO S/B-33580-M

Revision 12: Feb 28/2007 Page 9 of 12
 Turboprop Overspeed Governor Time Between Overhaul Table (Continued)

Governor TBO
210620 6500 Hours
210621 3500 Hours
210622 6500 Hours
210623 6500 Hours
210624 6500 Hours
210625 6500 Hours
210626 6500 Hours
210627 6500 Hours
210628 6500 Hours
210630 6500 Hours
210631 6500 Hours
210632 6500 Hours
210634 6500 Hours
210638 6500 Hours
210639 6500 Hours
210640 6500 Hours
210641 2500 Hours
210642 2500 Hours
210643 6500 Hours
210651 6500 Hours
210941 6500 Hours
210949 6500 Hours
210950 6500 Hours
210951 6500 Hours
210952 6500 Hours
210953 6500 Hours
210954 6500 Hours
210957 6500 Hours
210958 6500 Hours
210960 6500 Hours

Issued Jan 01/1982 TBO S/B-33580-M

Revision 12: Feb 28/2007 Page 10 of 12
 Turboprop Overspeed Governor Time Between Overhaul Table (Continued)

Governor TBO
210961 6500 Hours
210962 6500 Hours
210963 6500 Hours
8210-011 3000 Hours
8210-013 3000 Hours
8210-060 7500 Hours
8210-061 7500 Hours
8210-063 3000 Hours
8210-068 7500 Hours
8210-085 3000 Hours
8210-091 7500 Hours
8210-093 7500 Hours
8210-150 3000 Hours
8210-151 3000 Hours
8210-152 3000 Hours
8210-153 3000 Hours
8210-160 7500 Hours
8210-161 7500 Hours
8210-162 3000 Hours
8210-163 3000 Hours
8210-164 7500 Hours
8210-167 7500 Hours
8210-168 7500 Hours
8210-172 3000 Hours
8210-251 7500 Hours
8210-290 7500 Hours

Issued Jan 01/1982 TBO S/B-33580-M

Revision 12: Feb 28/2007 Page 11 of 12
 Auto Feather Valve Time Between Overhaul Period Table

Auto Feather Valve TBO

8905-002 4500 Hours
8905-004 4500 Hours
8905-006 4500 Hours

Pump Time Between Overhaul Table

Pump TBO
8210-076 3000 Hours
8210-077 1500 Hours
8210-079 3000 Hours
8210-092 7500 Hours
8210-094 7500 Hours
8210-096 7500 Hours
8210-176 3000 Hours
8210-177 1500 Hours
8210-178 3000 Hours
8210-179 3000 Hours
8210-180 3000 Hours
8210-181 7500 Hours
8210-183 7500 Hours
8210-184 7500 Hours
8210-250 7500 Hours
8210-286 7500 Hours
8210-305 3000 Hours
8210-306 3000 Hours
8210-307 3000 Hours
8210-308 7500 Hours
8210-309 7500 Hours

Issued Jan 01/1982 TBO S/B-33580-M

Revision 12: Feb 28/2007 Page 12 of 12