What to do about a stripped spark plug hole?

lndwarrior · #1 11-03-2015, 06:46 PM

I honestly know squat about aircraft engines, though I'm just starting to learn.

I have a severely stripped spark plug hole in my Lycoming engine. It is stripped so bad the plug literally falls out of the hole.

So what's the proper fix - a new cylinder? Or possibly a helicoil?

Fortunately this was a spare engine that was pretty much donated to me. I was getting ready to try and sell it when I discovered the problem.

Tia,
Gary

BobTurner · #2 11-03-2015, 07:50 PM

The engines come with helicoils. Sounds like yours came out? Make sure it didn't fall into the cylinder. Replace it. Make sure no sharp ends protrude into the cylinder.

Scott Hersha · #3 11-03-2015, 07:58 PM

Install new helicoil. A little tricky if you haven't done it before. Enlist the help of a local A&P who has done this before is my recommendation - and what I've done. Remove both spark plugs, move the piston to TDC. Use air pressure/vacuum to remove any debris that gets inside the cylinder after the new one is installed, and if you have a boroscope to make sure the cylinder is clean that would help. Took my A&P about 30 minutes start to finish.

Marklew · #4 11-04-2015, 09:25 PM

Hi Gary,
I am in northern CA and looking for an engine. What do you have? you can PM if you wish.
Thanks,
Mark