OFHG Gasket troubles - Bolt thread damaged (N55)

[bung206]

So I was doing my OFHG. I was putting it all back together but unfortunately as I put in the first bolt (the one that’s under the intake), I fucked up and put it in at a slight angle. As soon as it got harder to turn than I was expecting I stopped and took it out. Looking closely at the threads I can see the first 3-5 threads are kinda damaged. The rest of the threads are OK.

What’s the best way to fix this? If I slowly work in the bolt a quarter turn at a time, the backing it off, then back in and repeat this process until it’s all the way in will it be okay?

[rad_name]

Best case scenario, get a hold of a tap and run it down to clean the threads and hopefully they still have enough material in them to take the torque.

Worse case, drill out and bang in a heli-coil.

[Gangplank]

You'll need a tap & die set the right size. You thread the die on and it cuts new threads.

http://knowhow.napaonline.com/know-h...maged-threads/

[Mybimmer]

Yep use a tap. Don't try and fix it with the bolt. The alloy is soft and it won't work out. Clean the area and tape of all of the openings in the block before you tap the treads to avoid swarf shavings getting into the oiling system.

[bung206]

Ok - got a M8 tap with the exact same thread pitch and ran it all the way down - all good now!