While replacing my inner primary cover, torquing down one of the fastener bolts, using the recomended 25-27 in/lbs, stripped some threads in the bolt hole. Its #2 in the tightening sequence, center top. I was reviewing some "threads" on using the Heli-Coil product to repair the bolt hole and was wondering if anyone has used this or a similiar product for this task. Also which kit should be ordered for the best results. 2007 FXDB. Not all of the splines were damaged, just 1 towards the transmission case end, and the bolt wont simply pull out but wont torque either - it has free spin with a ratchet. Should I just loctite it and not be overly concerned at this point?

 

Helicoils work very good. I used one on a brake caliper on my Jeep when the threads in the knuckle stripped. Never had a problem with it after that.

I got it at Napa, what ever brand they use.

 

I've trolled the various threads, visited a vew thread repair sites, and watched a couple How To videos. It looks like I require the 1/4-20 Helicoil Kit and a 17/64 drill bit to repair this. One question I havent been able to find an answer on, or Im missing, is regarding the depth requirement. The Helicoil instructions have you placing it flush with the surface but isnt the inner primary fastener hole threaded all the way through?

 

Ok so Im reading about "Piggybacking" of HeliCoil Inserts on the Emhart website. Im not certain this is required but at least I know it can be done if required.

 

On a 1/4" bolt one would be enough.

 

They do make longer ones, at any rate i think you will find the instructions will tell you to install it one thread in from flush. you dont want the first helicoil thread poking up above the surface, it`ll pull out.

 

Thanks, I did miscalculate though. I brought a bolt with me to O'Reilly's to make sure I got the correct Helicoil Kit. I actually needed a 5/16-18 Kit and a 21/64 drill bit. I consulted a machinist and he informed me that a single insert should suffice, although I forgot to take into consideration that the hole I was tapping had about a 1/4" recess to accomidate a guide bushing so it wouldnt have allowed for 2 inserts anyways. The final result was excellent. The machinist also informed me that my problem was probably due to improper bolt maintenance. IE: Not cleaning the threads well enough - removing old loctite residual and such. I guess I need to invest in a good die set and acetone solvent for next time.

 

On my S and S 113 from the outside of the inner case is. 1 7/8" use an ice pick to send in the hole and mark exactly where it comes out. Then measure from the tip to the mark. Hope it works out good luck

 

I stripped the threads out the clutch inspection cover 5 hole. Only one got stripped my torque wrench failed. But I drilled it and installed a heli coil and have never had an issue since. Stop the leaking

 

Get the Craftsman 52105 40 piece Rethreading kit - I use this kit all the time to clean fasteners and their holes, worth every penny and Made In US.