SERVICE BULLETIN 227A
September 21, 1998

TO: All FAA-Approved Propeller Repair Stations, Owners, Operators, and Aircraft Maintenance Personnel

SUBJECT: Propeller Installation Mounting Torque

MODELS AFFECTED: All McCauley Propellers

SERVICE MANUALS AFFECTED: 730720, 720415, 710930, 780630, 701115, 761001, 810915, 790901, 860201, 810301, 880415, 890119, and CMM1100-1


This service information should be added to the appropriate McCauley Service Manuals until the next revision is issued.

Service Bulletin 227A replaces Service Bulletin 227 dated August 5, 1997. Lines in margin indicate changes.

All McCauley propellers have specified installation instructions and torque values for mounting hardware. The installation procedures require propellers to be installed with no lubrication or with lubrication. Installation with or without lubrication is engine specific. When a propeller is installed without lubrication, all mounting surfaces and threads must be clean and dry. When a propeller is installed with lubrication, threads, nuts and nut torquing surfaces are lubricated with grease (MIL-T-83483).

This information is located on the installation decal, A-2230-X, which is installed on the hub.

Torque for installation of fixed pitch propellers is contained in the aircraft maintenance manual. You may reference Table 1 for the correct torque for fixed pitch propellers.

COMPLIANCE:
Apply correct installation decal (if needed) and follow appropriate installation instructions at any propeller installation.

WARNING

Lubricated torque values may be used only when
specified lubricant is properly applied.

NEVER use lubricated values without lubricant
or
DRY torque value with lubricant.
Failure to use correct torque values or procedures
may cause stripped studs/nuts or loose mounting of propellers.

CONTINENTAL ENGINE APPLICATIONS

All propellers installed on Continental engines use lubrication on the mounting hardware at installation.

McCauley has manufactured three styles of propellers for the Continental engine.

Style 1: Hubs were manufactured in which the bolts extend through the hub wall. These hubs have a counterbore where each bolt protrudes through the hub. O-rings are installed in the counterbore prior to propeller installation. Propellers with this style hub use the A-2230-10 decal (Figure 1).

Style 2: Hubs are now manufactured with studs threaded directly into the hub wall mounting surface. Propellers with this style hub use the A-2230-9 decal (Figure 1).

Style 3: 3FF32C501 propeller models only use A-2230-7 decal (Figure 1).

FRANKLIN ENGINE APPLICATIONS

All propellers installed on Franklin engines use lubrication on the mounting hardware at installation. These propellers use the A-2230-9 decal (Figure 1).

LYCOMING ENGINE APPLICATIONS

All propellers installed on Lycoming engines use no lubrication on the mounting hardware. This installation uses a dry torque value. These propellers use the A-2230 decal (Figure 1).

GARRETT ENGINE APPLICATIONS
PRATT-WHITNEY ENGINE APPLICATIONS

All propellers installed on Garrett or Pratt-Whitney engines are to be installed with lubrication on mounting hardware. These propellers use the A-2230-7 decal (Figure 1).

PROPELLER INSTALLATION INSTRUCTIONS—A-2230
  1. Lightly oil O-ring and hub bore surfaces only.
  2. Propeller face, stud and nut threads, engine flange holes, and both flange surfaces must be clean and dry.
  3. Torque nuts 65 to 55 lb-ft.

PROPELLER INSTALLATION INSTRUCTIONS—A-2230-7

  1. Lightly oil O-ring and hub bore surfaces only.
  2. Wipe clean propeller face and both engine flange surfaces, then install propeller onto propshaft.
  3. Liberally apply grease, A-1637-16 (MIL-T-83483) only, to threads of studs and nuts; also to faces of nuts & spacers.
  4. Torque nuts 68 to 72 lb-ft. LUBRICATED TORQUE ONLY

PROPELLER INSTALLATION INSTRUCTIONS—A-2230-9

  1. Lightly oil O-ring and hub bore surfaces only.
  2. Wipe clean propeller face and both engine flange surfaces, then install propeller onto propshaft.
  3. Liberally apply grease, A-1637-16 (MIL-T-83483) only, to threads of studs & nuts; also to faces of nuts & spacers.
  4. Torque nuts 50 to 45 lb-ft. LUBRICATED TORQUE ONLY

PROPELLER INSTALLATION INSTRUCTIONS—A-2230-10

  1. Lightly oil O-ring and hub bore surfaces only.
  2. Propeller face , stud and nut threads, engine flange holes, and both flange surfaces must be clean and dry.
  3. Verify that bolt O-rings are properly seated in bottom of counterbores then install propeller onto propshaft.
  4. Liberally apply grease, A-1637-16 (MIL-T-83483) only, to threads of bolts and nuts and to faces of nuts.
  5. Torque nuts 50 to 45 lb-ft. LUBRICATED TORQUE ONLY

Figure 1. Decals


The installation torque for McCauley fixed pitch propellers
is determined by the bolt diameter.

Bolt or Nut
Diameter

Torque (DRY)
Pound-Feet

Pound-Inches
3/8
7/16
1/2
30 to 25
45 to 40
65 to 55
360 to 300
540 to 480
780 to 660

Table 1: Fixed Pitch Bolt Torque

TORQUING WITH ADAPTERS

Use proper calculations when using torque adapters to ensure correct installation torque.

If an adaptor or extension is attached to the torque wrench drive end and adds to its length, then the actual applied torque will be greater than the dial reading. The following formula should be used to find what the dial should read in order to obtain the correct applied torque:

Dial Reading= Torque Wrench Length (A) X Desired Torque/Torque Wrench Length (A) + Extension Length (B)

NOTE: If torque wrench reads in FT-LBS, then (A) and (B) must be in feet.
  If torque wrench reads in IN-LBS, then (A) and (B) must be in inches.

CAUTION:
It may be necessary to use various adapters in ertain applications.
Extreme caution must be exercised to ensure that
accurate torque is being applied for maximum retention.

APPROVAL: FAA approval has been obtained on technical data in this publication that affects product type design.

McCauley Propeller Systems | P.O. Box 5053 | 3535 McCauley Drive | Vandalia, Ohio 45377-5053 | USA
800-621-PROP (7767) | Telephone (937) 890-5246 | Telefax (937) 890-6001