Service Bulletin No. 642A
Incorrect Piston and Ring Combination
June 16, 2021
O-235-C, E & H series, and Factory Cylinder Kit P/N 05K23039
TIME OF COMPLIANCE
Within the next 10 hours of operation or next scheduled maintenance event, whichever occurs first.
REASON FOR REVISION: Deleted NOTICE “Only cylinders that …”. Added CAUTION and instructions for cylinder replacement before the Procedure section. Revised Step 5 in the Procedure section. Revised title and Step 1 in the Warranty Instructions
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