I just put my 22re back together and fired it up after having the head serviced. I had issues with the spark plug hole threads over the #4 cylinder and asked them to fix it... but I guess they didn't.

The truck fired up first try and runs and idles well, but I can hear the air leaking and even see some oil that I put on the threads of the spark plug bubbling around it's seat when the engine is running.

I assume any way to fix the threads in the head would involve removing it again... which I am not willing to do. Any help finding a way to seal the plug without removing the head would be greatly appreciated.

My ideas so far:
1. Use a crush washer so that the plug will seat onto that sooner and create a seal?
2. Maybe a bead of high temp RTV around the washer to head mating surfaces?
3. Some kind of thread locker on the actual spark plug threads? Or mayber even teflon tape? Not sure if either would be worth the risk of debris ending up in the cylinder when removed again.

Any advice or prior experiences with a similar issue would be really helpful. Thanks in advance.

 

I believe that you can get a helicoil to repair it . You should be able to do it on the truck. Just make sure to put plenty of grease on the tap, to catch the filings and clean and re-grease the tap often.

 

This, assuming that you can tap it without competely boogering it up. It would be ideal to take the head off, but its worth a shot on the truck. Just make sure the tap is going in straight

 

So, after a few heat cycles... the plug seems to have sealed itself. I'm thinking now, maybe I should just leave it alone until time for a tune-up. Any thoughts?

 

i would throw on a little teflon tape. it would probably se3al fine and would make removing in the future easier

 

Not gonna hurt anything, other than maybe a little less power

 

Has anyone tried using teflon tape on spark plug threads before? I thought of that, but thought it would probably just burn up from the heat. I almost think I should just leave it alone unless it starts leaking again. It seems that screwing the plug in and out is most likely eating a little more of the threads in the head each time.

 

I wouldn't even worry about the loss of power from the exhaust blowing past the plug... I just want my fuel economy to be as good as possible... and the plug not sealing seems like it would adversely affect my mileage as well.

 

A plug not sealing doesn't just let exhaust out it is also a vacuum leak that will cause that cyl to run lean and hotter than it should be.

 

yeah... and it still sucks in through the tail pipe because of it... guess I need to do something about it soon. Any thoughts on the teflon tape or crush washer idea? I would rather steer clear of tapping and installing inserts with the head on.

 

If you throw a bunch of crush washers on it you are lowering the compression of that cylinder due to a larger squish zone, and with the spark further away the ignition of fuel/air will be less efficient.

 

I was thinking one crush washer would fill the gap... it already won't screw all the way in so that it will seat properly. Anyone ever try teflon tape on a spark plug?

 

In case anyone is interested:
There is a special tool... which is essentially an adjustable tap. It goes past all the threads inside the cylinder head, then it expands and taps the threads from the bottom up. This means it starts with undamaged threads, so you know it will stay straight... and also pulls all of the metal shavings up and out with the tap... without even using any grease.

This tool solved how crooked my spark plug was from being badly cross-threaded. This was definitely the best fix... and it took 5 minutes and cost me 10 dollars.

Thanks again for the replies though. Yotatech is such an excellent resource for anyone with one of these trucks.

Cheers

 

Nomad, I've never heard of that tool but it sounds like it would work. This sounds much better than crush washers or teflon because it actually fixes the problem. Good post

 

Any info on this tool? I just got a new motor to find that the #4 plug doesn't really get tight when I'm threading it in.