I am currently in the final stages of rebuilding a 93 lt1 in a z28. I stripped the treads in the crankshaft while putting on the crank pulley. I was wondering if a helicoil would be a sufficient fix for this problem. Also, I need to know the proper torque specification for this particular bolt. Any help would be appreciated.

 

How deep are they stipped?

 

Try a longer bolt, that may catch some good threads.

 

how in the hell did you manage that? I torque the crap out of mine, I think it was like 80 foot pounds, so the damn thing wouldn't come off again, like it did last year... You must have only caught a couple threads to do that bang up job!

 

Its easier than you would think. We did it to my car too, before going to a stroker. If you dont tap the balancer on far enough before you try to start threading it will rip out the first few threads.

 

WTF??? No do NOT install the balancer that way! Damn! You gotta use the Kent Moore installer for that! The bolt isn't long enough to use it to pull the balancer hub onto the crank. I guess if you cant get a hold of the puller, installer tool, go to the store and get a longer bolt, so that can get more threads before you start torquing it. Then, when that bolt bottoms out, take it out and use the one that will stay in the car to pull it the rest of the way on.

 

The way I install mine is by using a peice of all thread threaded fully into the crank, then I get some washers and nuts and press the thing on there, remove the allthread and install the bolt.

 

Installing a hub by "pulling" it on via the threads is how cranks get stripped in the first place. Hubs should be installed using a threaded rod that is threaded onto the crank, then using a nut and bearing to pull the hub onto the crank. This way the threaded rod takes the stress and not the crank threads.

 

Another way to do it without the "proper" installation tool is to use a series of long to gradually shorter bolts and thick washers to pull the hub on. That way you'll be able to have plenty of thread engagement. It's worked several times for me already.

 

Thanks guys. How I managed to strip the threads was repeatedly removeing the pulley and then putting it back on. the threads at the front of the hole in the crank take about 70% of the torque when tightening. once those stripped the rest went along after a couple of attempts to put the pulley back on.

 

would a helicoil work on this application.