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Discussion Starter · #1 ·
Yesterday I finished installing rear brakes w/all new parts: hold down hardware, springs adjusters etc. I reinstalled the original shoes as they had been replaced and still had the manufacturers printing on them. I had a serious struggle to get the shoes into the outer groove of the backing plate where they seat. Installed pins and springs, top springs. To install bottom spring had to slide bottom of shoes in, hook spring, then use adjuster to get shoes back out to where the would seat in the backing plate. Never struggled with drum brakes like these. Question: Could the hardware I ordered by incorrect i.e. too much spring tension? Anyone else encounter problems with reassembling the brakes. Final thought: Also installed new emergency brake cables and loosened them as much as possible. Could the em. brake cable cause the problem. Thanks for any feedback.
 

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1957 Chevy Bel Air Convertible; ZZ4 w HEI ign; 700r4; 9" rear w/3:50 gears; pwr disc fr w drum rear
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There isn't a groove in the backing plate where pads "seat". The pads float and rest against metal pads in backing plates (which need to be lubricated at time of pad install) so that pads can operate without binding. If you have a groove in your backing plates they might need to be repaired....or replaced with a better set. Repair involves welding grooves and grinding flat.
 

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Discussion Starter · #3 · (Edited)
There isn't a groove in the backing plate where pads "seat". The pads float and rest against metal pads in backing plates (which need to be lubricated at time of pad install) so that pads can operate without binding. If you have a groove in your backing plates they might need to be repaired....or replaced with a better set. Repair involves welding grooves and grinding flat.
Thanks Ace 57. After another go'round with the rear brakes I discovered what you have just told me. Shoes do not sit in the recessed groove on the backing plate, but on the face of the plate as you described. I was working from a diagram in the shop manual and it was difficult to see how the shoes sat on the plate. Another question though. Once I figured out correct shoe placement, I installed adjusters and completely retracted them. Even then, I have to use a little force to get the drums on, and cannot turn the drum by hand. I am going to put the tires back on and see if they rotate then. Is it normal for shoes to fit this snugly? They came with the car and appear to be new. You can still read the print on them. Zero groove in the drums. Sorry for being clueless here, but haven't worked on drum brakes for many moons. Thanks for any advice.
 

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Trifive Automotive Electrical Wiring Expert
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Do the shoes fit the arc of the drums? In the old days, it was common to grind down the shoes to fit the arc of the drum, after it was turned. Maybe the shoes are oversize.
Take a shoe off and put it inside a drum and see if it touches the drum from end to end.
 

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Something is not right if you have the adjusters fully retracted and still cant get the drum on. I would not install the tire. You may have an even harder time afterward getting the drum off. Any chance you can post a photo of the brake install?.
 

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Discussion Starter · #6 ·
Do the shoes fit the arc of the drums? In the old days, it was common to grind down the shoes to fit the arc of the drum, after it was turned. Maybe the shoes are oversize.
Take a shoe off and put it inside a drum and see if it touches the drum from end to end.
Will get a picture posted tomorrow. Amazingly, the install appears to be identical to the diagram posted by Pops (I think). But maybe with a pic, someone who knows drums better than me can figure this out.
 

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Need to look at a pic of your install, are the shoes installed right you should have a long/short shoe installed correctly
 

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Discussion Starter · #8 ·
Need to look at a pic of your install, are the shoes installed right you should have a long/short shoe installed correctly
Here are some pics of brake shoe install. Long shoe is back, short forward. Photos 2 and 3 are to show shoes touch backing plate stud at top and adjuster is fully retracted. (Sorry for the blur; best I could get.) New emergency brake cable is slack. Spreader bar touches at both ends on front shoe and emergency brake lever on back shoe. These shoes were installed when I bought the car and looked very good so I reused them. Any chance PO used wrong shoes or oversize shoes?





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Discussion Starter · #9 ·
Do the shoes fit the arc of the drums? In the old days, it was common to grind down the shoes to fit the arc of the drum, after it was turned. Maybe the shoes are oversize.
Take a shoe off and put it inside a drum and see if it touches the drum from end to end.
Posted pics today Don. If it is correct, going to disassemble and check arc of shoes in drum. Obviously, if install is correct, problem is at drum/shoe matchup.
 

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1957 Chevy Bel Air Convertible; ZZ4 w HEI ign; 700r4; 9" rear w/3:50 gears; pwr disc fr w drum rear
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Those photos stink. maybe you could back it up and take one from a couple feet away. You're making it hard to help.
 

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When I was doing work as a state licensed brake mechanic way back when, we would grind the shoes to match the drum if necessary.
There should be .007" to .009" clearance at the leading and trailing edges of the shoe when holding it in the drum, prior to assembling it on the car.
If there is no clearance -- or worse yet, a gap at the center of the shoe -- the brakes will grab.
I have no idea how drum brakes are being properly serviced these days without shoe arch grinders.

With the brakes fully assembled on the car, the adjuster fully retracted, and the parking brake cable and wheel cylinders applying no pressure to the shoe, the drum should turn without the shoes providing much friction at all.
Automatic adjusters are not original parts. Perhaps some part is different from the original design, causing issues?
 

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Something is up. As far as I can tell from looking at the top photo, the lower part of the shoes are protruding well beyond where the should, almost like its the wrong shoe or something is not assembled correctly. You should double check the shoes. Stock shoes are Nos. 228 and 9 but I forget which one is front and which is back and I am pretty certain at least with the No. 9 shoe, that number 9 has been superseded.

Can you take some closer photos. I cant tell if the emergency brake cables are pulling the shoes outward or something else.

Re-arching the shoes was something that was done when you turned down the drum. The re-arching trimmed a bit off of the leading edge of the pads so that the friction material seated fully in the drum. This would have happed anyhow through use as the leading edges wore down but you would not have full braking until the pads wore down. Re-arching the shoes was discontinued because of the asbestos dust the process created. Unless you know a private someone with a re-arching machine, you are going to have a hard time finding a actual shop to do that kind of work as most got rid of their machines years and years ago.
 

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Just as a matter of asking, with the emergency brake/handle in the retracted position, do you have slack in the cables at the rear brake or are they pretty tight? If tight, you might crawl under the car and loosen the adjuster nut (look for a U shaped piece that the rear cable loops into with a sort of J hook with one end treaded and a nut, this is where the adjustment is) to slacken them up and see what that does. Generally, once the rear brakes are installed and adjusted, then you adjust the emergency brake.
 

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Discussion Starter · #15 ·
Just as a matter of asking, with the emergency brake/handle in the retracted position, do you have slack in the cables at the rear brake or are they pretty tight? If tight, you might crawl under the car and loosen the adjuster nut (look for a U shaped piece that the rear cable loops into with a sort of J hook with one end treaded and a nut, this is where the adjustment is) to slacken them up and see what that does. Generally, once the rear brakes are installed and adjusted, then you adjust the emergency brake.
Thanks to all for your input. Problem solved. Dug through shop manual and found there are 6 contact points on backing plate. These are to be rust free and lightly lubed. Duh!! I painted the entire backing plate and because of that, shoes would not seat properly against the backing plate. They hung up on the paint I guess. Wire wheeled the contact points to a shine, dab of brake grease, assemble, drum pops right on. Ace 57 clued me in on where and how the shoes contact the backing plate. Thanks to him and everyone who gave help. I have now made it a point to research before disassemble. I did not mention,in my first post, about painting the entire plate, so no one could steer me right in that area. Live and learn, but this one was a tough lesson.
 
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