tc1234c
Well Known Member
Last Saturday after compression test it was hard to get the spark plug in #1 cylinder. After a few tries I noticed a corner of the thread came off. After pulling it out a little I noticed it is an insert. Only after I came home and read about it I learned it is a special Helicoil insert. I must distorted the first few threads. What worse is that this insert has serrated edge and requires special tool to install. Our local FBO does not have the tool. I checked with Hangar Tool Box (tool rental) and they don't carry this special tool. The installation tool and the tap set cost $1,200! Now I may have to take the cylinder off and ship it to an engine shop to get it fixed . Of course the coil costs only $8 and it is quick with the special tool. The advise I received from the mechanic is not to use too much antiseize and clean the thread often. This way will prevent the problem happening again.