93 festiva spark plug problem

[muddevil01]

I have a 93 festy with a b3 with only a couple mods such as cold air intake and custom exhaust. The problem I'm having is that the spark plugs keep coming out or coming loose.Is this a common problem? They seem to thread in ok and tighten up good.I am just trying to figure this out any help would be great.

[TominMO]

That's pretty odd; I wonder if you have stripped threads on the head.

[muddevil01]

I suppose it is possible they don't appear to be I shined a light in there and they looked ok.I can't imagine that all of the plug holes are stripped. the plugs start easy and go in straight and even. This is like something I've never seen before. I'm just trying to see if this is a common problem and if so what has everyone else done to fix it.

[MONSOON]

Is it all 4 plugs that keep backing out? Are you torqueing them enough?

[muddevil01]

So it has only been #2#3#4 yes I'm pretty sure that I am tightening them enough as I am a mechanic by trade but I have never had this problem before

[MONSOON]

Hmm thats a puzzler. Ive never seen or heard of that happening. Others will chime in though Im sure.

[muddevil01]

I sure hope so I'm getting tired of carrying a plug wrench with me at all times

[FestYboy]

are you SURE you're using the propper plug seat? (crush ring)

[blkfordsedan]

That is pretty odd.........usually, it's the opposite problem and the plugs seize and won't come out. Especially #1 cylinder. The only other motors I've seen with that problem were a dual-plug 2.3L Ford and the notorious 4.6/5.4 Modulars that blow the plugs out due to insufficient thread length. Have you tried different brands of plugs?

My guess is it has something to do with the expansion/contraction of the head or sloppy threads. Maybe the alloy composition in the casting was slightly off from the factory? Maybe the head has been too hot once and now the metal is fatigued and expands more than it should? Maybe the threads were cut slightly oversized due to quality control issues?

These are just guesses.........they may not even be possible causes. I wonder if wrapping the threads with something would work. Teflon tape? Maybe Stainless Steel tape? Surely someone here has had this issue before. You could always use JB Weld..LOL

[muddevil01]

Yes I am using an autolite 63 with the crush ring so what gives I had an 88 626 and changed the plugs numerous times and never had this problem

[FestYboy]

just making sure...

when you pull any of the plugs, is there any evidence of damage? (detonation, other psysical damage)

[blkfordsedan]

Honestly, I would say the threads are worn/bad. If you bought the car used, you never know what a P.O. has done. Considering its an aluminum head, they may have stripped the threads during an install and ran a thread chaser through them. Have you looked at the crush rings to see if they're getting the proper amount of crush when torqued?

[muddevil01]

I have only had the car a month or so it has a little over 200,000 when I did the initial plug change #3 plug had the electrode burned clean off but other than that no other signs of damage so is a heli-coil my only option besides a head swap

[Flyin4stroke]

thread locker....

[FestYboy]

^ umm NO (bad BAD idea)