stripped spark plug hole

[Jeremy]

there are no threads left in the spark plug hole. we have looked at and tried a lot of tools and repair kits but nothing wants to work well. i dont want to do any more damage to this head untill i have a little more info.

it is a DOHC so you have to try and work on the hole in a 6" deep sleeve. most of the tools that come in the repair kits wont work because #1 the tool is to big around to fit in the sleeve, and #2 the tool is not long enough to reach the hole at the bottom of the sleeve.

what would a shop charge to fix something like this?

what have some of you done to fix this?

are there any kits or tools that you would suggest?

 

[Tacoma]

Know any machinists? Of course, I'm guessing you'd rather leave the head ON the car...

 

[shmoesmith]

there is this goo stuff you can get at checker that you coat the inside of the hole with and then coat a release agent onto a spark plug....you coat the hole, then 'screw' the sparkplug into the goo and let it sit for like 20min...then the release agent lets you unscrew the sparkplug and the goo solidifies into a rockhard substance that exactly matches your spark plug threads and bonds to the metal on your head......the larger the screw, the stronger the epoxy...if i remember right, with large screw it could hold 80+ ft/lbs of torque. I used it, and it works great.

 

[Jeremy]

hase anyone ever used time-sert thread repair. it looks like it is the best option for the do-it-yourself guy. solid inserts not coil inserts. now if i could only find some place that has this kit.

 

[Samuraiman]

Spark Hole

hase anyone ever used time-sert thread repair. it looks like it is the best option for the do-it-yourself guy. solid inserts not coil inserts. now if i could only find some place that has this kit.

Hey I use the solid insert all the time. Also I took a tap and welded a bolt on it special for use on those type of deep socket holes. GOOD LUCK. make sure you put bearing retainer on the insert.

 

[Jared]

Seems like drilling into the hole would shed some generous metal shavings into the cylinder. My instincts are telling me that this could be bad somehow... Like when one of them gets stuck in a valve and causes it to burn up. Or when it gets lodged between the piston and cylinder wall. Or when it ends up in your catalytic converter. Or...

Just be sure to get it all out. You might even figure out a cool way to blow air into that cylinder while you drill by getting that intake valve open. I dunno, just food for thought.

Jared