I recently shot a plug from my 2000 f-150 5.4 v8. I bought a kit that taps out the hole for a steel insert. The mechanic that installed it crossed the threads on the inside of the insert that the plug goes into. I cant get a new plug to tighten up. It's the 2nd one back from the front on the driver side, so at least it's easy to get to. I'm now faced with removing the insert. Has anyone ever successfully removed one before? I really don't want to have to pull the head. If I can get the insert out I'm hoping I can then install a new insert and fix this problem.

 

Your best bet would be to contact the maker of your kit, they would possibly have a tool for that operation. I doubt that you're the first to have it screwed up.

 

For reasons I'm not going to get into, I only need to keep running this truck for 8 more months. I have 121,000 miles on it now and will be looking for another vehicle in the spring. After that it can go. I decided that I would take a risk. The new plug would go in the whole way but wouldn't get tight. So, I coated the threads of a new plug with JB Weld. I then put it into the insert and ran it all the way in. I left it set for 24 hours. I've run it now for almost 200 miles and so far my truck has never run better. I just hope it holds out. I figure if it doesn't, then maybe the insert will come out with the plug. If not I'm back to where I started from and I go to the Ford garage. So far so good, and it only cost me 5 bucks for the jb weld. One thing I would like to know is how hot the threads on a plug actually get. I have talked to a lot of mechanics who have heard of, or used jb weld themselves on other vehicles in areas around the combustion chamber. Wish me luck!

 

Probably a lot hotter than JB weld can hold. I forget what it said on the JB weld. Isn't it only like 200 deg. or something like that?

 

MarineTex is a better product for use on or in an engine The surface has to be thoroughly cleaned before application though.
Good luck with your repair, I hope it holds.

 

Well, the JB Weld didn't work. It gave up after 300 miles. Next step (which should have been the first step) use an easy out to back the insert out of the head. Easier than I thought it would be. Clean the threads in the head. Put in a new insert. Put in a new plug...good as new! Might get another hundred thousand miles.