So I went to start my truck today and the back spark plug on the drivers side blew out. I just bought the truck and it has newer plugs and coil packs so I'm assuming the person who installed those cross threaded the hole and made it weak.


My question is what the heck do I do from here? I don't really want to tear the head off of the truck or tear the truck all apart. Is there a product out there that is designed to fix this while the head is still on the truck?

Any help will be greatly appreciated, thanks.

 

You can get a helicoil insert to repair threads, but those require that you drill and tap the original hole to accept the insert.

I don't know how you could drill and tap in that space (I think the driver's side is better than the passenger side from what I remember when I had my 5.4L).

It would be tough to get all the cuttings out of the cylinder. I suppose you could vacuum and inspect with a borescope.

 

Yea of course the dang thing had to be in the very back!!!!

I'm trying to do this with the minimum amount of taking my truck apart. I'm pretty mechanically inclined, I just hate doing it.

 

use the serach and you will find that has happend alot I think even napa sells a repare kit too

 

This is a common problem, do a search on it. Here is a link to a good write up on fixing it: https://www.ford-trucks.com/forums/9...th-photos.html

From most people on here the Time-Sert kit is the best way of doing this. Also go to there website for info on their repair.

 

Yea I saw one of the threads and they are kind of hard to read. Alot of replying without any info (atleast the thread I saw).

I did find some kits at advanced like the Dorman Kit, it was about $75. which is way more than a heli coil kit so I was wondering if anybody here has had any experience with them?

 

Dorman and Timesert are the best, helicoil is the worst, if it is one of the front 4 a shop should do it for $300 or less, one of the back 4 could easily be double that.

 

Of course its the back one. Very far back on the drivers side. I'm going to try and get a dorman kit tonight and get this thing installed tonight, in my driveway with low light conditions!!!! I can hardly wait, it sounds like a blast to do.........................

 

This may be a dumb question, but is there a next size spark plug I could go to? and maybe tap the hole one size bigger?

 

Since I recommended Helicoil, I was just wondering why it is the worst. I work as a design engineer and we send tools on top of drill bits 20k ft into the ground at temperatures like 300 degrees and pressures to 25ksi. Of course the inserts are not open to the drilling fluids or anything, they are embedded in the tools.

Will a Helicoil allow the explosion to blow by? I can see how that might be a cause for concern.

 

basicly a helicoil used for this type of repair ends up just unwinding and repopping..

the proper repair is one of the above mentioned kits that is designed exactly for the repair.

 

A Timesert kit is your friend. The kit isn't cheap but its the right tool for a permanent job. The repair sleeve is aluminum so it expands and contracts with the head. The install tool cold forms the last few threads so the insert doesn't back out.

 

Helicoils are a great invention and I frequently use them, but they do have a tendency to back out of aluminum parts when exposed to lots of thermal cycles. The difference in expansion rates of aluminum and steel contributes. Not every time and it takes a while, but enough of an issue to make them less than ideal for repairing spark plugs in aluminum heads. My personal experience was 3 plugs fixed with heli-coils, 1 failed.

The time-sert is the next generation of threaded inserts. They are solid, and are expanded during installation - forming an interference fit that is much less likely to back out. Yes, they cost more, but are more reliable in critical applications. I've NEVER had a failure.

And I find them much easier to install correctly - expecially in difficult to see locations.

Check them out - a great "tool" to be aware of!
++ TIME-SERT Threaded inserts for stripped threads, threaded inserts, thread repair stripped sparkplug's, Ford sparkplug blowouts, threaded inserts threaded, repair stripped threads, stripped threads, inserts threaded inserts, Ford spark plug repair,

 

Well I went out tonight and bought the Dorman kit from advanced auto parts. I think it was 56.99. To me it almost looks to easy, but I will try it. I will post later if it worked or not.

Basically you just screw this tapered deal into the old hole, thread it till its tight, then you screw this elongated spark plug into the first guy and its done............. We will see. Supposedly the part taps a new hole while containing all the shavings, your just supposed to screw it in once and not back it out.........

I will post an update later.

Thanks for all the replies.

 

Good luck with your repair. What type of motor and year is your truck?