Spark plug stops threading HELP!
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Spark plug stops threading HELP!
I just put new heads on my LS2 c6 and when I thread (by hand) my spark plug into cylinder 4 I only get about 2 turns before it just stops. When it gets to the point of stopping I can’t even remove it by hand because it’s too tight so I put a plug socket over it and then remove it by hand. I don’t want to try tightening it with a socket wrench because the last thing I need is a new head. Does anybody have a solution to this without removing the head?
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Did you try a thread chaser ??…I’d blow or better yet suction out any debris that makes its way into the CC with the piston at TDC…having a borescope helps to verify everything is out helps…is the plug threads ok ??
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Just bought a thread chaser online so I’ll give it a go. The threads are brand new (brand new heads) so I’m not sure why I can’t get it to thread. Every other plug went in with ease. Stuck my phone camera down there and everything looked fine. No material in the plug hole or anything. I’m thinking maybe there was a burr or something between threads stopping it. Ill provide updates when I get the thread chaser. Any tips?
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From: Cape Coral, Florida
Just bought a thread chaser online so I’ll give it a go. The threads are brand new (brand new heads) so I’m not sure why I can’t get it to thread. Every other plug went in with ease. Stuck my phone camera down there and everything looked fine. No material in the plug hole or anything. I’m thinking maybe there was a burr or something between threads stopping it. Ill provide updates when I get the thread chaser. Any tips?
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had the same thing on one plug after I ported and polished the heads on my engine teardown......the thread chaser did the trick. Good luck.....let us know what you find out.
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grease the fk out of it and after each 1/4 turn against light resistance remove it very slowly and carefully try not to wiggle it up and down when turning and remove the shavings of metal each time you think theres metal on it,
if any metal gets inside that cylinder its going to be big problems, hopefully its just a tiny burr
Run same or a loose fitting thread through carefully with grease after finished to remove the rest of any tiny bits of metal flakes
if any metal gets inside that cylinder its going to be big problems, hopefully its just a tiny burr
Run same or a loose fitting thread through carefully with grease after finished to remove the rest of any tiny bits of metal flakes
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Like the others have posted, you probably have a burr in the threads keeping you from screwing the plug in
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I did it!! Thread chaser and some red multi purpose grease made it unbelievable easy. 15 min fix taking my time. Followed everybody’s advice and did about a quarter turn before backing off and repeat. Cleaned up the inner bore with a q tip. Didn’t take out much material at all. It must’ve been a burr because once I got past the initial point of interference I was able to thread it pretty easily. Only removed the oil dipstick and the plug wire. Thank you to everybody who helped!!
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I did it!! Thread chaser and some red multi purpose grease made it unbelievable easy. 15 min fix taking my time. Followed everybody’s advice and did about a quarter turn before backing off and repeat. Cleaned up the inner bore with a q tip. Didn’t take out much material at all. It must’ve been a burr because once I got past the initial point of interference I was able to thread it pretty easily. Only removed the oil dipstick and the plug wire. Thank you to everybody who helped!!
Cool !!