DATE: September 5, 2002

Lycoming Service Bulletin No. 552 requires replacement of crankshafts in some turbocharged Lycoming TIO and LTIO-540 engines rated at 300 horsepower or higher.

DATE: July 1, 2002

MODELS AFFECTED

All Lycoming aircraft engines.

TIME OF COMPLIANCE

At engine start in cold weather.

In extremely low temperatures, oil congeals, battery capacity is lowered, and the starter can be overworked. Improper cold weather starting can result in abnormal engine wear, reduced performance, shortened time between overhauls, or failure for the engine to operate properly.

Supersedes Service Bulletin No. 529 A

June 10, 2002

MODELS AFFECTED

All Lycoming aircraft engines employing new or overhauled “AN” rotary fuel pump model series RG9080, RG9570 and RG17980, including:

Supersedes Service Letter No. L180 A

Models Affected

To all Owners and Operators of Textron Lycoming Aircraft Engines

Engines in aircraft that are flown only occasionally may not achieve normal service life because of corrosion. This occurs when moisture from the air and products of combustion combine to attack cylinder walls and bearing surfaces during periods when the aircraft is not used. The procedures for combating this condition consist of coating the vulnerable surfaces with rust inhibitive compounds as herein described.

Supersedes Service Bulletin No. 545

October 2, 2001

MODELS AFFECTED

I. All Textron Lycoming TIO-540-AJ1A and IO-540-AC1A5 aircraft engines shipped from the factory before October 30, 2000, unless Kit P/N 05K23081 has been installed.

II. All Textron Lycoming TIO-540-AJ1A and IO-540-AC1A5 aircraft engines that have had Kit P/N 05K23081 installed before May 1, 2001.

TIME OF COMPLIANCE

I. Inspect within the next 10 hours of operation and replace within the next 50 hours of operation.

DATE: January 26, 2001

MODELS AFFECTED

O-235 aircraft engines operated under the authority of the French Direction Generale De L’Aviation Civile (DGAC.)

TIME OF COMPLIANCE

At owner’s discretion.

The French DGAC has reported a significant number of O-235 cylinder barrel failures in France. These failures have initiated from corrosion pits at the base area of the cylinder.

Supersedes Service Letter No. L197

January 19, 1988

Models Affected

To all Owners and Operators of Textron Lycoming Piston Aircraft Engines

In order to minimize valve sticking problems, procedures recommended in this Service Letter should be followed. Depending on the degree of intensity, sticking between the valve stem and guide can severely restrict the valve's opening and closing movements. A sticking valve condition is often identified by an intermittent hesitation, or miss, in engine speed.

DATE: January 11, 2001

MODELS AFFECTED

All O-540-F1B5 model engines installed in Robinson R-44 helicopters.

TIME OF COMPLIANCE

At overhaul.

Textron Lycoming has revised the counterweight tuning to lessen vibration characteristics for the O-540- F1B5 model engine installed in those Robinson R-44 helicopter which use the new Robinson fanshaft P/N C007-5.

DATE: December 20, 2000

MODELS AFFECTED

Textron Lycoming VO-435-B1A model engines.

TIME OF COMPLIANCE

At overhaul or whenever the accessory drive gear and shaft assembly P/N 76327 is disassembled.

Any time the accessory drive gear and shaft assembly, P/N 76327, is disassembled, replace the three standard dowels, P/N 76323, connecting the gear and shaft with oversize dowels P/N 76323-P15.

Supersedes Service Instruction No. 1502

December 19, 2000

MODELS AFFECTED

All Textron Lycoming IO-360-L2A aircraft engines.

TIME OF COMPLIANCE

Whenever the engine has vapor related problems, or at owner’s discretion.

To reduce the possibility of vapor related problems in aircraft employing IO-360-L2A model engines, the flow divider should be modified into an inverted flow divider.