Have stock model a rear end. Fitting up 40-48 brakes. Have read all the literature on how to..... Les Andrews etc. Tilted backing plates forward to clear wheel cylinder inlet at spring hanger, notched blah, blah, no problem. Now took off 1/8th inner drum lip and also on backing plate, lip. Not even close to fitting. Rubs, then drum binds when I tighten the axle nut. Took a little more off drum and backing plate lips, retryed, better but not even close. I now have less than a quarter inch of backing plate lip left, and am 1/8 below the outer drum lip on the machined inner drum lip, and a axle shim and almost there but still not quite!!!!! Seems the brake shoes may not have enough surface on drum now? Wtf? Read like 10 different articles all saying take 1/8 of each surface and done. Baffled!!! Help!!!! Posted from the TJJ App for iPhone & iPad
Just like Junkyard kid said, take some off of the shoes out edges carefully. The get some drum taper shims jsut for good measure. Pretty common.
I was aware of the shoe bevel thing, but I'm just fitting with no shoes still and seems I've had to take off a **** load more than anyone in any articles, and still no fitty. Posted from the TJJ App for iPhone & iPad
Tried with shims too. How much was left of your backing plate lip when done and how far did you go with the shoe surface lip on da drum? Posted from the TJJ App for iPhone & iPad
i just did 1/8 inch on the drums. You are useing the hydraulic hubs right? If you are i got no ideas at this point.
You took 1/8 outta the drums (basically flushing it with the outer drum lip) and none outta the backing plate? I'm at 1/4 off backing plates and 1/4 off drum 2 axle shims and now it sins free with axle nut tight, but ****! Have I taken too much outta the backing surface on drum or am I ok being that the shoes stand off the backing plate a bit? Hydraulic hubs yes. It baffles me why I would have to machine off so much more. Why? Posted from the TJJ App for iPhone & iPad
You took 1/8 outta the drums (basically flushing it with the outer drum lip) and none outta the backing plate? I'm at 1/4 off backing plates and 1/4 off drum 2 axle shims and now it sins free with axle nut tight, but ****! Have I taken too much outta the backing surface on drum or am I ok being that the shoes stand off the backing plate a bit? Hydraulic hubs yes. It baffles me why I would have to machine off so much more. Why? Posted from the TJJ App for iPhone & iPad
heres a possibility...sometime in the last eighty years, someone had an axle key break, and score the taper surface. instead of buying new axles, they machined the taper maybe0.060" and stuck it all back together. that would cause your problem.. when ive done this conversion before ,it has been necessary to take more than the recommended off to get clearance, but as long as everything still sits where it has to..should be fine.
By what you describe you done every thing right, i wonder if some one didn't sell you some bogus parts. The backing plates are easy to identify, but i don't know about the drums
My recollection from when I first did my A banger back in the sixties, was that I had to make a pretty healthy br*** flat stock shim on the axle taper and eventually that spaced the drums out far enough w/o any other clearance-ing of the drum or backing plate. I used 46-48 hydraulics all around and matching front spindles. Another trick used back then was to flip the rear backing plates side to side leaving the cylinders on the bottom. It was better for shock link clearances for routing the steel brake line, but harder bleeding out, with the bubbles in the fluid wanting to float up and the bleed point being lower. The flipping plates required moving/switching around the cylinders and shoes, as I recall, so the brakes worked properly.
The axle being machined at some point could've a possibility. So here's a couple questions. Are shims ok? Or will they wear and cause big problems down the road? Second, if it recommends 1/8 machined of the inner drum lip (brake pad pad surface) and I had to take a quarter, will the pads be ok still or am I fooked? Posted from the TJJ App for iPhone & iPad
If the shims space it all back out to the right dimension, the lip removed should not matter. It just means the "lips" will not overlap like they were intended to do. Is that a problem? Can't see why except for dirt, dust, water, etc. More than one shim chan be used (I really don't know the limit on layering them). Properly installed, they don not wear as nothing rotates on them. My 2 cents
Criminal, true if spaced out correct lip removed wont matter but for dust etc. no prob there, concern is that the extra removed on the drum lip where the shoe pad runs is my concern. Possibly the part of the pad will be off the surface. Matter? Not sure. I was of the same thought on the shims, they move with the spline so no worse than the actual spline wearin out. Posted from the TJJ App for iPhone & iPad
Well, they stay "with" the spline and the spline does not move. And they spline should not wear out if properly installed and torqued. So, if the drum was too narrow for the shoe, just bevel the shoe or it will just wear a groove on the inside edge of the shoe. The shims were my friend.
It wont matter. Your a is a lot lighter than the car it came off of and the fronts do most of it anyways. Itll probably just wear in. test them in the dirt to see if they lock up.
I don't recall having any problems using all four corners off a donor 46-48 Merc station wagon on my 31 A in 58 or 59. I had the drums turned, new linings riveted on the shoes, and arced, put kits in all the wheel cylinders, and used a 53 or 54 MC/ pedal ***y. Used the rings on the front and slotted the mtg holes in the rear backing plates. I do recall the line into the wheel cylinder behind the spring perch/shock mount was tight.
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