driving home from work today and BOOM. when i checked under the hood, one of the spark plug boots was 3/4 the way out of the cylinder. When i pulled out the boot, the plug was attached. Checked out the threads on the spark plug, and there were bits of metal in between (from the threads inside the cylinder). I have a temporary fix with a new spark plug down in there, but i know the threads inside that cylinder are shot. I know the permanent fix would require tapping a new hole.
My question is can i do something like this myself? I can handle minor repairs in my garage, but this sounds slightly more complicated (and way easier for me to screw up).
Anyone have a ballpark idea of how much a repair shop would charge for something like this? I would THINK it wouldnt be extreme (tap a new hole, insert a helicoil, screw in spark plug), but who knows.
The heli-coil kits work well if done right. I used one years ago on a Chevy Beretta that my sister owned in High School. I did it on the car in the drive way, used a shop vac to suck out any chips that may have fallen in the cylinder when I was done. While I know not the best way,some say the head should be removed, etc. It was a cheap easy fix that lasted her over a year until she sold the car. She never had another issue, and we saw the car driving around our small town many years after.
your on the right track ..good luck ,happen to my buddies toy last week ..
Crap, hadn't heard about this on the Jeeps. Maybe the high compression hot rods but not a Jeep.
What age/size of engine and approx mileage?
I have a 2001 4.0 6 cyl with about 59,000 miles and just hope I'm not due for that little surprise.
Can this be caused by too much torque installing the plugs and stripping the threads or maybe not being set up tight enough? Or will the plugs have a tendancy to work loose if not torqued correctly?
Kind of like the greenhouse told me when my house plants weren't doing too good, either I was watering them too much or not enough.
Too tight going in can strip the threads - most of the time you'll feel it starting to pull then.
Too loose they can unscrew part way, then cylinder pressure blows it out the rest of the way.
Look at the plug that came out - see if it only has foreign metal on 1/2 or all of the threads.
I'll bet it was one of the 2 hardest, #1 or #2.
Thousands, maybe millions, of heads have been saved with Heli coils.
Grease the tap!
In the future to help prevent crossthreading - slip a short piece of vacuum hose over the top. Use that to position the plug and use it to turn it at least 1 turn. If it's trying to crossthread, the hose will slip off. Do not use a wrench to get it started.
It's no wonder the country is falling apart - stupidity abounds!
That sage advice bears repeating. I usually thread my spark plugs all the way down with my fingers and only use a 3/8" ratchet drive for final tightening. Using a 1/2" ratchet is just asking to overtighten/strip the spark plugs.
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