Stripped threads? What to do...
 

I have 2 sets of bolts not screwing in. The two bolts on my primary fuel rail screw in a bit, get tight and then loosen and pop out again. I noticed the bolt threads were chewed up, so I decided to get new bolts. Before that tough, I tried another bolt, the same size thread, and that wouldn't screw in either, which leaves me the believe the threads are stripped in the hole?

Attachment 492328

Is it safe to helicoil that part? Should I just get a new one? What is it even called (the plastic thing that the primary rail screwed into)?

I also have two bolts on the turbos that are doing the same thing ( tightening then getting loose) but the bolts are fine because the screw into other places no problem. These are the long bolts that connect the turbos to the engine-turbo manifold. Can I helicoil the manifold threads? I don't want to buy a manifold and a set of gaskets...

The plastic piece is actually just a spacer, the threads are part of the engine. I would remove the spacer and inspect the threads, retap them.

Should I just retap the same size thread? Know what size by any chance?

Remove the bracket and clean the threads out. You mat be able to use slightly longer screws and not have to fix anything.

There are pictures of the helicoil process in my build thread.

But for small hardware you could probably just drill and tap for slightly larger hardware. And not have to deal with inserts.

You have lots of options. Start with those that do not require permanent modifications.

I can't use longer bolts because the bolts won't even go past the first thread. But I'll try cleaning and tapping. Thabks