ORIGINAL: Mike Connor
ORIGINAL: combatpigg
How does a liner get turned out of place in an engine?
A lean run causes the engine to get hot which can cause the head bolts to be loose. Loose head bolts can let the liner turn. That is what I was told and it sounded good to me.
I never had it happen to one of my engines though. I can't think of any other explanation unless it was just put together wrong.
Thanks for helping out mike......
Thats basically it. Steel bolts - aluminum case. If the engine gets hot (realllllly hot) .... the bolts will loosen up. And, usually the glow plug gets toasted. So when you go to change the glow plug, the entire head button and sleeve rotates when you try to tighten a new plug in place.
Tends to happen more with the bar stock engines, but does happen with the other engines as well.
Fix is fairly easy. After re-aligning the sleeve, Tighten the bolts back down (gently, this is still an aluminium case). Run the engine for a few minutes, shut it down, and then check the bolts again with the engine still just slightly warm.
Also........ first run afterwards, use a 9x7 prop to let the engine unload, and to ensure it dose not get hot again.
Bob