Service Instruction No. 1132 B

Supersedes Service Instruction No. 1132A

June 18, 2010

MODELS AFFECTED

All Lycoming Opposed Series Aircraft Engines with Magnetos.

TIME OF COMPLIANCE

During Pre-Flight Inspection

A basic magneto drop-off check based on engine speed is typically done during the pre-flight inspection to determine the loss of engine speed that occurs when magnetos are switched from BOTH magnetos to one (LEFT or RIGHT) magneto. The maximum drop-off limit is specified in most Lycoming publications as Revolutions Per Minute (RPM) from a stated engine speed.

Service Bulletin No. 591 A

Supersedes Service Bulletin No. 591

May 10, 2010

MODELS AFFECTED

All Lycoming engines equipped with a rebuilt Kelly Aerospace Energy Systems turbocharger manufactured between January 2007 and June 2009 as per the part effectivity in Table I and per the serial number effectivity in Table III found in the attached reprint.

TIME OF COMPLIANCE

Within 10 hours of engine operation or at the next maintenance event, whichever occurs first.