Turbo to exhaust manifold helicoil size? Or thread inserts?

[Spoolin4Ever]

One of my turbo to manifold bolt holes is cross threaded from the guy I bought the turbo from. What size helicoil do I need?

 

[JusMX141]

10mm x 1.25. You'll also need a sharp 13/32" drill bit in addition to the HeliCoil kit.

 

[Spoolin4Ever]

10mm x 1.25. You'll also need a sharp 13/32" drill bit in addition to the HeliCoil kit.

Does Harbor Freight carry a good enough one or what is a good place to get it?

 

[donniekak]

I used to repair threads in all of the turbine housings that go on my car, and i made a decision. Using nuts, and bolts is a much cheaper, and actually better solution. The reason nuts, and bolts are better, is that if the nut happens to seize on the bolt, just use a breaker bar to break the bolt in half. Then like magic the two halves of the bolt come out from either end, and no threads to mess with.

 

[Spoolin4Ever]

I used to repair threads in all of the turbine housings that go on my car, and i made a decision. Using nuts, and bolts is a much cheaper, and actually better solution. The reason nuts, and bolts are better, is that if the nut happens to seize on the bolt, just use a breaker bar to break the bolt in half. Then like magic the two halves of the bolt come out from either end, and no threads to mess with.

Which sizes should i get?

 

[donniekak]

Which sizes should i get?

Length is going to be varied, but i use m8 bolts, and nuts. They fit through the old m10 holes with no problem, can provide plenty of clamping force, and if they fail, it doesn't take superman to break them in half.

 

[Spoolin4Ever]

Length is going to be varied, but i use m8 bolts, and nuts. They fit through the old m10 holes with no problem, can provide plenty of clamping force, and if they fail, it doesn't take superman to break them in half.

Why does the length vary if all 4 bolts are the same size for this application? You kinda thru me off with that one.

 

[sbeck]

Have you tried a thread chaser or a tap before a helicoil? Those are much easier to do than a helicoil. Cast is pretty strong and should be able to be tapped unlike aluminum that requires helicoils.

 

[99gst_racer]

Is it even possible to run a Helicoil inseart in a turbine housing bolt hole? Wouldn't it not allow the bolt to pass completely through the flange on the turbine housing because of the little tail used for installing?

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I've always thought it was poor design to use a fine thread on a heat-cycled cast steel part. Many years ago, I had a Bullseye housing with 3 broken bolts. As soon as we got them out, we drilled and tapped the housing for a larger diameter coarse thread, and never again had any issues.

Why does the length vary if all 4 bolts are the same size for this application? You kinda thru me off with that one.

Length can depends because not everybody is using the same manifold. Stock manifold, FP manifold, aftermarket tubular manifold - they all would require a different length bolt.

 

[Spoolin4Ever]

I took it to the machine shop and had it permacoiled/helicoiled. Did all 4 holes at once, so I don't have to come back. Some people were saying once they helicoiled it they never had to worry again that it worked great. It was $41 to have it done, not bad.