Repair threads with Helicoil

[@johndustin158]

what size drill bit was it that you used to drill the hole before making new threads

[@BernardBouchard-qq9kq]

Go to 1/2 20 .

[@Chagrin223]

Was this a 7/16-20 bolt like typical sbc?

[@rupbret]

Yes, the threads were repaired to 7/16 - 20 so same Chevy bolt could be used

[@thewhiteelephant]

Any reason you didn’t remove the balancer prior to repair?

[@rupbret]

I really didn't need to, as the tap and drill bit were long enough to be used with it in place. The balancer was not in the way, it would have taken extra effort that was not necessary. I recommend you verify if removal would make this easier for your application.

[@thewhiteelephant]

@@rupbret My challenge is that I don’t want to pull the motor. I am going to try to tap some new threads in there as I can still see some good threads further in. I purchased the longer ARP bolt, and hopefully I wont have to drill it. Appreciate the feedback.

[@rupbret]

@@thewhiteelephant I didn't have an option to work on engine in place as there isn't much room in Corvette bay to do that. If you can leave the engine in and get a straight shot at it. I think that would be worth it.

[@Stilllwatersundeep]

Where did you get your Heli coil kit

[@rupbret]

Tacoma screw products, I believe it was $30, however Amazon has multiple kits with more than 1 size for $30

[@RoyMeraki]

does helicoil works with square or acme thread ?

[@rupbret]

That's an interesting question. I actually tried doing some research before answering, and maybe someone can correct me. I do not think Helicoil will work for either of those thread types.

[@RoyMeraki]

DADams Garage i just did some research & i dont think so now