Crossthreaded 5.3 Sparkplug?solutions?

[email protected] · January 5, 2010

So much for the "even a monkey can change a chevy's plugs" for now i'm having to humbly rank myself lower than the IQ of the common chimp. I can only get the rear plug on driver's side 1/2 way in. Anyone got any experience using a thread-chaser? Is it a big gamble?

I envision the thing following the "new" incorrect path further off center as it goes deeper in the cylinder porthole potentially ruining a fine (?) aluminum head. Should i just buy a manual and remove the head and just go get it machined for under 50 bucks?

How many hours does driver side head removal call for? I dread that the exhaust manifold may leak afterward more than anything i think. Any good advice is welcomed ...thanks...

[email protected] · January 5, 2010

hmmm, i somewhat new to this site so far i haven't been able to get any advice on a mechanical related (see 5.3 crossthreaded plug ) issue here on this "GM Technician"column. Is this normal? This topic seemed to fit in here. I'll check in later and give all the cylinder machinist specialists a chance to get done laughing before they respond!

dlstewart01 · January 5, 2010

Depends how bad its cross threaded. When it became known it was cross threaded, did they STOP or keep cranking it down. If it is not too bad, there is a possibility the threads can be chased and saved. If not a machinist will need to drill the hole oversize, rethread and put in a helicoil restoring the hole to original size. Some one real good can do this with out removing the head.

http://www.emhart.com/products/helicoil/repkit.asp

http://www.roadstarmagazine.com/modules.ph...cle&sid=233

[email protected] · January 5, 2010

can a helicoil blow out at high rpm? I typically redline this truck at a frequent rate, so i didn't want to get caught in a situation where i feel like she's gotta be babied.

dlstewart01 · January 5, 2010

can a helicoil blow out at high rpm? I typically redline this truck at a frequent rate, so i didn't want to get caught in a situation where i feel like she's gotta be babied.

Well back when I worked in engineering for General Electric. ( in the 70s) we would some times install steel helicoils in aluminum as it gave a much stronger coupling. Will it blow out I don't know but I doubt it, as its stronger than the aluminum threads. If a filler is put in the spark plug hole to catch the aluminum from drilling them flushed out the head would not have to be removed. But if you want to remove the head then there are other solutions as well....

Also see....

http://www.timesert.com/html/sparkplug.html

http://www.fulltorque.com/sparkpluginserts...CFQuenAodSX27KA