Stripped harmonic ballancer bolt........

[Ghost]

Ok went to put the new bolt in the end of the crank and the treads stripped. I think someone does not watn me to go to Tellico this week. Ok so what are my options? drill and tap for bigger bolt? The one in there was a 1/2-20. This happend once b4 and I just put a longer bolt in and tapped it further in. So what is the next size up? 5/8? So It looks like I will have to get my machinest friends to help me get this fixed. Any advice here would be greatly appreciated.

 

[ADam J]

Ghost,

I did the same thing about a month ago when finishing up my stroker. I bought a replacement bolt, same size as original, and ran a tap to clean out the threads on the crank. I used a healthy dose of red lock-tight and tightened it down. I was supprised how easily it stipped out.

My understanding is that the bolt only serves to keep the balancer from walking off the shaft from vibrations. So as long as it's in there tight ( regardless of size) it should be good.


My mistake was using the bolt as a pully pusher :banghead:
I learned to tap the balancer on instead of stipping those fine threads...

-Adam-

 

[Casper]

Ghost,
Since there is no real pressure on the bolt that holds the harmonic balancer on, and the bolt is mainly there to keep the balancer from backing off, you can do this:
Run a tap the exact size of the bolt to clean the threads as best you can, then put in a helicoil and new bolt. I have done this before on jobs where the pressure is not directly pushing on the bolt. You would be surprised what these little devils can do......
Any of your local auto part stores should have a selection. But the best bet is NAPA...

Casper

 

[PaulJ]

First thing is not to use the bolt to pull the balancer on. Most likely there are just a few threads stripped. You may be able to clean up the threads and just use a slightly longer bolt. Just don't try to pull the balancer on with minimal thread engagement.

 

[Ghost]

NO all the threads were stripped. I had done this b4 and just retapped with a longer bolt. But this time I was trying to torque it to 80 Lb-ft. Got a tap and there is a new grade 8 9/16th bolt in there. Hope it works.