Service Instruction No. 1191 A
Supersedes Service Instruction No. 1191
September 28, 1998
All Lycoming aircraft engines.
TIME OF COMPLIANCE
As required to determine cylinder compression
The condition of the working parts in the combustion chamber of a cylinder can be determined by measuring the static leak rate of the cylinder as compared to the leak rate through an orifice of specified size. This is accomplished by attaching a differential compression measuring device, which incorporates the orifice, to one spark plug hole of the cylinder while the piston is at top center of the compression stroke.
Get It Exchanged
Use our Engine Exchange Program to order a new, rebuilt, or overhauled engine to experience more airtime and less downtime.