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740 Turbo - Spark plug won't stay in, is being struck by something

Hey all, thanks to all for the water pump advice, worked like a charm.

Latest problem I got is a spark plug (no. 1 or 4, closest to the grill) that won't stay in long. After several days of short commuting, the plug is loose. Today as I checked it for tightness I was alarmed to find that it was not only loose, but being contacted by something. Layman's guess is the piston. Needless to say, it seems like just tightening it would be a bad thing, since that would make things worse. Can the car be driven at all in its current state, or should it be taken in immediately? If this is about pistons and valve clearances, this seems out of my league as far as fixing things myself? Or is it?

Any and all advice would be much appreciated.

A
Reply to
Skonnie
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Upon further inspection, I can't confirm that an object is striking the plug. It might just be air presssure sucking the plug in and out. At any rate, a short 5 mile trip loosened the plug again after re-tightening. The "ticka-ticka" noise coming from the engine is quite noticeable. Any recommendations on re-threading the case? Or any other solution?

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Reply to
Skonnie

For the possibility of striking the plug, be sure you are using the right heat range. Too high a heat range means the plug extends farther.

The hole can be Helicoiled. Your easiest approach is to have a professional do it; many will do it on the engine. If you have trouble with that, we can lay out the process.

Mike

Reply to
Michael Pardee

Sounds like the threads are damaged. IPD makes a kit to repair this, it's sorta like a Helicoil as far as I know. The other option is to swap the head with one from a wrecker but that's a LOT more work.

Reply to
James Sweet

The second option is likely not an option for me. I'll try #1. Keep finding gunk on the plug when I take it out, this may have been a problem to the previous owner as well. The plug screws in well by hand albeit loose, but after applying a quarter turn with a socket wrench, the same problem pops up after a few miles of driving. I will try IPD's kit, will update.

Thanks, all.

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Reply to
Skonnie

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