What size thread are the parking brake shoe bolts?
Thanks,
Stephen
Bump
Stephan, they are 1/2" fine thread.
Rick
If the bolt hole is wallowed out can it be safely fixed by drilling it oversize and then installing a heli coil?
Stephen
i guess so. i was not sure and helicoils are not available in my country so i put a thin sleeve over the bolt to stop it pulling in too far and tightened the nut up.
bump
I drilled and tapped the hole to 5/8" then screwed in a piece of threaded rod, pinned it in place then ground it flush. I then used a backing plate removed from an opposite housing for a drill guide. When I was done I could see I had accomplished what I had set out to do; accurate locating of the anchor bolt. My new hole was not in the center of the slug. Drilling wallowed out holes changes the original location.
The only other good way to fix a wallowed out hole would be to weld it shut, but it's been my experience that welding on some unknown cast steel or iron material makes it so hard you can't drill it and I didn't want to take a chance on a six rivet housing.
A helicoil will work. My dad had a machinist install one in the backing plate of one of the original axle housings on his '17 touring. Although the original threads in the hole were worn/stripped, the hole itself was not really wallowed out. I didn't witness the procedure but I don't believe he had to close the hole first and then drill a new one. I think there was enough "meat" left to work with so all he had to do was drill/true-up the hole prior threading it for the helicoil.
You will need (via Amazon is where I got mine)
-Helicoil 5528-8 0.5-20 Inch Fine Thread Repair Kit
-33/64-Inch Bit
-The better part of a $50 bill
Drill out the existing hole, being **very** careful to keep your drill squared up to the axle tube and relative the existing hole. Install, trim the excess. Took longer waiting for the package to arrive from Amazon that it took to do the job. Side benefit was that the Helicoil freshened up the threads on the bolt nicely.
Apologies; I have better photos somewhere of the install process if you need it, but not with me. In the photo below you can see the installed Heli just peaking out...
Before this, mine was so bad on the Ruckstell side I could push the bolt through with my thumb.
If the threads are just worn or stripped a helicoil will work. Timeserts are much better if you are familiar with them. I got a 1/2" fine thread Timesert kit for repairing front axles before I got the Stevens front axle repair tool, which by the way will repair brake anchor bolt holes.
Thanks everybody. This one is wallowed out bad enough where the bolt can be slid right into the hole. I don't think it is bad enough where the heli coil would not work though.
Stephen