crank threads..

[Premium72]

well it seems some how i screwd up the threads on my crank while changing my balancer out. is there a fix for this? other than a new crank? im not to sure about tapping it out an re threading it. whats you guys thoughts on this? im losen my mind!!!...thanx. w.

[jacobs]

Can you just run a tap in and clean up the threads? I don't advocate this BUT 1950's and maybe early 1960's small blocks wern't threaded - just a press fit. I never had any problems with my old 1957 283 balancer moving around.

You can always drill it out and heli-Coil it.

[Premium72]

would the helicoil be ok? i was thinkn if doing this,. its seems when i put in the cam i grabed the wrong bolt(coarse thread bolt) and it may have messed up the threads, but it did work. then when i went to change the balancer the puller i had messed up the threads on the outside. now the bolt has to be in a good ways before it will thread in. im gettn kinda disscouraged about this.....im gana try an work on it some more this sun. any help is greatly appreciated as always. thanx. w.

[jacobs]

Heli-Coils have always amazed me. I've never been able to pull one out although there may be other thoughts out there.

Another possibility is to clean up the present threads and install a stud using red locktite and screw it all the way into the crank. Then use a nut and washer to hold the balancer tight. If you try this method, be sure to use a torque wrench on the nut and torque it to specs. If it will tighten that tight w/o pulling out, I'm sure it'll be ok.

[woodridge]

The stud idea is good just make shure that it is a grade 8 or better. Heli coils would also work well. In many high stress applications good threads will be drilled out and a heli coil installed, it is much stronger. In the transportation core class I teach I demonstrate this by drilling and tapping a 3/8X18 hole in an aluminum block, screwing a #8 bolt in through a spacer and tightening it until it pulls the threads out of the block, repair it with a heli coil and repeat the bolt and spacer using a fresh bolt and this time the bolt pulls into.
Heli-coils are very good.

[Premium72]

AWESOME!!.. this has made my night. my stepdad(whom im coming to find doesnt seem to know as much as i thought.(that might be my fualt )) told me ill prolly need a new crank. the stud idea sounds great. thanx fellas. im in better spirits now. w.

[70GMCer]

I learned the hard way buy using the bolt to press in the balancer and it broke off inside the crank. I'll use the tool next time. Now I don't say this is a good idea, but I left the balancer on without removing that broken bolt. The balancer aligns up and have been using the truck over a year now (off and on) without any movement. The early small blocks were pressed on. Although they didn't have the power outputs the newer ones have. I think maybe that's why the bolt is used. You're lucky that you were able to get the bolt out. I'd try re-threading and get a grade 8 bolt as mentioned before.