Stripped bolt hole on engine block/case!

Noticed moisture/oil on the lowest, for most bolt for the engine block/case(not sure what the proper termanology is). Turns out the threads in the block, are now part of the bolt! Time, wear must of taken its toll. What is the proper way to fix this problem. Do I have a shop Heli coil it? Do I have to split the cases and redo the gasket? Thanks

Sounds like Heli coil time.....:worthy:


Is this one of the bolts that hold the two halves of the case together? If so, I would think that yes, you'll have to split the case.

You have 3 options here. 1st, you can try the correct size thread tap to try and clean out the threads left from the bolt. I've had a simular experience with the oil filter cover. The engine case metal is harder than the bolt metal, so this can work, if you're slow and careful.

2nd, a Heli-coil kit should work just fine. you can pay a shop, but if you have a drill, it's not hard to do. Just take you're time and don't over tourque the heli-coiled bolt.

3rd, Some would say this is the best fix. A machine shop can drill out the stripped hole, and press in a cylinder of metal. Then they would drill and tap the "plug" back to the correct size. I believe this would be the most problem free fix, but would require a complete teardown, a bit more $$, and longer down time.

The 3rd idea is a bad idea in my opinion..:worthy:

A heli coil is stonger then the original hole..If it's installed right..It's made from stainless steel....


A slightly longer bolt might work, you could prob. cheat with a helicoil and put it in with the cases together- just drill and tap the whole shebang but make sure the insert clears the outer hole completely.

I'd prob. try it.

I'm notoriously cheap and lazy, though.


I did the same thing to mine and Heli-coiled fine now. I'm just very easy with it. The thing to do is get a torque wrench so it doesn't happen again.

I'd try this first. Carefully chase the threads with a bottom tap, that is a tap with no starting threads and flat on the end just like a bolt. Do it slowly and carefully using oil on the tap, withdrawing the tap after a couple of turns and blow the debris out of the hole, repeat until the tap bottoms lightly, make sure all the shavings are removed. You can do this by using carb cleaner with that little straw on it, insert the straw into the hole and flush. Install a bolt that is 2-3 threads longer with a dab of thread seal on it and do not overtighten, snug is good. You might get lucky.

I hate when people post with a problem and then dont post the result! So here it is. I looked for a stainless bolt just like factory but longer. Found one close, but not the same head. I used stainless washer and new longer bolt to simulate factory. Since the threads were on the factory bolt, I could see that it had grabbed 3-4 threads. I CAREFULLY tried to thread the new longer bolt in its place. After getting it to thread, I could see that I was grabbing a lot of new threads! With the new bolt and washer I was able to grab 5-6 new threads with LOCKTITE. Should be good to go another 15 years!:crazy::lol: :lol: ;):worthy::confused:

Great job :lol: .

Glad to hear you got it fixed.:lol::confused:


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