If the cylinder heads are on the engine, you will need to add air pressure to the cylinder to hold the valves in place. Our example is the Craftsman 47089 compression test kit using the 14mm long ...

Airborne Flying Services of Hot Springs, Ark., developed and now offers the Valve Wizard, a set of three valve spring compressor tools for Lycoming O-235, O-290, IO/O-320, IO/O-360, AEIO-360, O-435, ...