Service Instruction No. 1129 D
Methods of Checking DC Alternator and Generator Belt Tension
Supersedes Service Instruction No. 1129C
July 23, 2015
All Lycoming direct drive engine models
TIME OF COMPLIANCE
During periodic maintenance inspection of the engine and at anytime the alternator or generator belt is installed.
REASON FOR REVISION
Corrected NM torque values in Table 1
If correctly installed, tensioned and checked periodically, the DC alternator or generator drive belt will give very satisfactory service. However, an incorrectly tensioned belt will wear rapidly and can slip and cause a decrease in electrical energy output.
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