stupid spark plugs

[Rent-A-Cop]

im just havin one heck of a day with the jeep today, i noticed it was idling rought today when i started it, turns out one oy the spark plugs came out :eek: :eek: by its self i might ad, and most of the others were trying to do the same. anyone had this happen, or is it just one of those days??

[andy d]

uhmmn, put 'em in tighter next time. never heard of stripping out the threads on a cast iron head.

[johnwom]

A friend of mine just told me the same thing happened to him with his '87 BMW 535. I had never heard of that happening before but this was his first time changing plugs and I think he was understandably cautious about stripping out the aluminum head.

I'm with Andy, this is iron so give it a good twist.

[Rent-A-Cop]

i thought i was gonna break the plug off cause i tightend up so good, but they backed right out wehn i fired it up, im thinking the PO might have gotten the wrong plugs, casue it does take a while to fire it up, maybe not gettin enough spark

[sailingjeep]

That's weird. I want to hear more.

[Rent-A-Cop]

what more would you like to hear? if i know it i will try to answer it

[sailingjeep]

I just had never heard of such thing, I'll be interested to hear what was causing it or your solution.

[Rent-A-Cop]

maybe its all the rust on thr spark plug threads. im not sure, ive never had this problem on any of my other vehicles ive owned before,for now i plan on cleaning the threads up and reinstalling the plugs, if that doesnt help i might try new plugs.and if that doesnt work i might have to resort to using some type of thread locker on them. would that be a bad move??

[reddog]

Thread locker would not be good. If the plugs are the correct ones, the plugs threads are OK and they will not hold sounds like the threads in the heads are bad. But all 8??!?!? Something strange is going on here. If in fact all eight are stripped in the heads then the best fix would be Helicoils. Depending how many miles are on the motor you may consider getting rebuilt heads and trading yours in as cores. Please let us know what happens. I am curious also. Strange.... very strange...

Kerry

[Rent-A-Cop]

all were loose, but only one keeps backing out, its the #3 that is the problem. maybe its just the plug, i plan on doing a complete rebuild of the engine. i might just see if i can get a reman. if its cheaper

[joe]

Start with fresh clean plugs not ones with rusted threads. You might also have a good look at the threads in the block. If they look rusted use a tap smeared with grease and run it through to clean the threads up.
If #3 is still backing out I'd suspect the hole's been cross-threaded at one time. Does #3 screw in evenly, firmly and straight? Oh...and don't use a thread locker of any kind.

[Rent-A-Cop]

yup, it screws in staight and even, doesnt stick while screwing it in. im lost on this one

[79cherokeechief]

does that spark plug still have that crush washer on it. I think thats what keeps the plug from backing out I could be wrong.

[Rent-A-Cop]

im pretty sure that it doesnt have a crush washer. i dont know if any of the others do,they were justa lil loose. #3 is the only one that was about to fall out of the head.