Hello - I am an infrequent poster, but really want to thank everyone for the great information you have shared over the years. I have learned a ton (well, maybe a 3/4 ton). I have a '51 3/4 ton that had worn out rear brake drums, so I hunted all around and finally found a used pair that were in decent shape to replace the old ones. The problem I have now is that I am able to mount the new drums, but they drag on the linings of the brake shoes (they aren't super tight, I am able to turn the drums by hand easily but I hear the linings scrape. They are Huck brakes, the truck is on jackstands and the drive shaft is disconnected. I don't want to turn the drums (per Nate's advice) and I can't adjust the wheel cylinders any more to retract the shoes. The linings are thick; I suppose I could have thinner linings installed, but I am loathe to remove the shoes, pay for new linings etc etc. Will this scraping just wear off within the first few miles of driving the truck with the new drums on, or are there any tricks/tips that anyone can share? Thanks a bunch, Ed
Brake shoes linings ! Good day to you Ed. I have Huck brakes to on my 1/2 t. truck and went for the same prosedure ! If the linings are to tight near the drum at all time and get warm when driving things aint good. Normally a very slightly scrapping sound is acceptable as the Huck only have that one cyclinder and the linings do not follow the drum nicely all the way through. The new shoes are they a standard fit or did you had a workshop to glue on new linings ? Then look very closely to the hight/thickness of the new linings if they measure the standard hight , compare with the old onces? You could measure the inside drum aswell. Sometimes these old drums are out of center and not round anymore , then you have to have a machine shop to deal with it. Did you cleaned or replaced the old small parts for new onces , springs ect. ? If rear brakes check if handbrake wires releases in a proper way, if they are not to tight so they keep the brake in action all the time ! Drum should glide very easely over the shoes when getting it in position. Hope this whas of any help Martinius.
brakes dragging Thanks Martinius, The linings look quite thick, perhaps 1/4 inch or so. Not sure if that is standard thickness. I had replaced the wheel cylinders; once I had decided the old drums where shot I decided to go ahead and get new cylinders anyway. The new drums appear to be round, the dragging sound in pretty uniform as I turn the drum. The parking brake cables are fully released, so that isn't the issue. I get my preferred strategy would be do just drive the son-of-a-gun until that scraping sound goes away (the linings wear down) but I am worried about any strategy that seems to easy...
Dragging Shoes Hi Ed ; 1st. , make sure there's no residual cylinder pressure by opening the bleeder screw , if nothing spurts out and you're 100 % sure the various parts and return springs are properly installed , button it up and drive it, make 10 + gentle _full_ stops from 15 ~ 30 MPH them remove a drum and see if the shoes are wearing in one one end more than the other , I'm betting this will be the case and you just need to break them in gently , in a few miles they should stop dragging , try to make only short runs so the drums never get hot to the touch . When do we get to see pictures of this truck ? . it's never to old , battered or dirty to garner approval here as WE LOVE TRUCKS .
brakes dragging Great, thanks Nate! I'll give it a shot and report what happened. It would be great to be able to put rebuilding those brakes in the "finished" catagory. I'll post some pics as well. She's not pretty at this stage of the rebuild, but she is practically all I've got these days. The ex-wife told me either the truck goes or she goes. I do miss her sometimes
I guess "radiusing" (? sp) brake shoes is right up there with black and white television. We used to have a very large caliper (vernier type, not disc brake) that one measured the drum diameter after turning or replacing. This measurement was adjusted to on a drum type sander that clamped the shoe and swung on a pivot the correct distance to give the shoe the same profile as the drum. We didn't know or worry about the cloud of asbestus dust it produced. If a drum is bigger than the shoe radius the shoe just touches in the middle and if smaller the shoe just touches on the ends. A real "Motor's" manual, mid 50's or older, gives the very best procedure on Huck brake adjustment; it's not real quickly done.
Brake Shoe / Drum Interface That was called " arcing " and pretty much all Shops had the stand up typ of arc grinder when I were a lad , in the 1970's I nearly got fired for firing it up to put the finishing touch on a brake job with badly fitting shoes.... Dust ? so what ? now we know better .
" Right Up There With..." I forgot to mention : Arcing the new (or relined) brake shoes was necessary because back when they used proper , full thickness lining , the shoe didn't fit the drum properly ~ if the drum fit , you could just drive it and re adjust the shoes as they bedded in , this ensured a longer life brake job but was time consuming . so production shops all had arc grinders . Anyways , Even was mentioning long forgotten things like vibrators & tubes in radios , dial telephones and so on , of course I still have these things and use them daily..... .
