Rear brake woes
 

I'm installing rear brakes after getting them back from Snyder's, completely rebuilt. I removed the radius rods to make it easier. I positioned the service brake lever forward to clear the fork in the radius rod and put the drum back on, forgetting to return the service brake lever to the upright position. The emergency brake band hung up a little, but I managed to get the drum on. But I couldn't move the lever back after the drum was on.
I took the drum off again and easily moved the lever upright, but now I can't get the drum over the service brake shoes. I noticed that the shoes are expanded further when the lever is upright than when it was pointed forward, which seems to be the issue.
Your suggestions would be most appreciated.

Re: Rear brake woes
 

Maybe a picture of the backing plate/shoe without the drum might help :)

Re: Rear brake woes
 

Here's a picture.

Re: Rear brake woes
 

Brattons has a good diagram of how the brakes go together. See https://www.brattons.com/REAR-BRAKE-...tinfo/AD%2D16/

With the lever horizontal the cam that activates the shoes would not be in a position to move the shoes. with the lever vertical, make sure the cam is situated between the rollers and is facing the correct way. Make sure the cam moves back and forth and has a small amount of grease on it. With the drum off, pull the lever to see if the cam is moving the shoes correctly.

If the drum has not been turned to true it the drum may be too small to fit the shoes. Also if the shoes are not centered the drum may not fit. The vendors sell a tool for checking to see if the shoes are centered. New linings on the shoes may need to be sanded a little to make the drums fit.

The shoe linings should have bevels at the leading and trailing edges.

Re: Rear brake woes
 

Coyle,

How far on does the drum go? Is it the service brake shoes and linings that are holding the drum off or the E-brakes? If it is the service shoes, there is a last little bit of installation movement on the service shoes that gets the head of the roller pin to ride properly on the roller track. I dealt with this yesterday.

The head of the roller pin and the track are not visible. The only external indication that I had that the roller pin head was in the right position on the track was: When looking straight at the upper shoe roller, the face of the cam shaft and the lower roller...the faces of the two rollers are set back about an 1/8" from the face of the cam shaft. At first, they were all three flush with one another.

There is a brake tool from vendors that looks like a grip off a pistol. It has two hooks on it and is made to give the user plenty of leverage to remove the shoes or install the shoes easily expanding the springs. If the properly shaped and tension springs are used, the shoes can be removed and installed by hand...unless you're aging.

Also, the long spring holding the shoes needs to be installed correctly so that e-brake carrier does not set on top of the middle part of the spring. On our car the long spring was not shaped correctly and was in the way of fully seating the e-brake carrier. I had ordered new springs from Snyders to solve the problem. The springs on the car were also much stiffer than the new ones.

Hope this helps you. The devil's always in the details!

Re: Rear brake woes
 

The E-brake shoe is assembled incorrectly. The cotter pins should face the other way or they will rub on the brake drum.

Tom Endy

Re: Rear brake woes
 

If the shoes are expanded farther when the arm is forward than they are when it is upright maybe check to see if the actuating cam is spun around in its holder ?
Pull the E brake assembly off to fix the pins like Tom suggested and maybe get another pic of the service brakes without the E brake on.

Re: Rear brake woes
 

Here's another picture with the brake drum on as far as it will go. When I try to push the brake lever back, it expands the shoes further and won't go all the way back.
If I push the lever all the way back before trying to put the drum on, it still won't go on, as the shoes are too tight. I sanded the ends of the linings, but that didn't seem to help.

I'm reluctant to take everything apart again (a lot of work), but am learning toward the notion that the cam is past its stop. What do you think?

Re: Rear brake woes
 

I see that no one has mentioned yet to screw the brake wedge in quite a ways to retract the shoes (at the bottom). If you don't do that, you might not ever get the brake drums back into place. Did you turn those adjusting wedges in?
Marshall

Re: Rear brake woes
 

Sorry, I forgot to mention that I turned the adjusting wedge counterclockwise to its stop before starting to put the drum back on. That's not the problem.

Re: Rear brake woes
 

Did you check the operation of the brake with the drum off? Did you check to see if the cam is located correctly with respect to the rollers and its proper orientation?

Re: Rear brake woes
 

It's early, I've only had one cup of Joe. But, perspective is important. Cause I'm easily confused, LOL.

We appear to be working on the left rear wheel, as viewed from the driver's seat looking forward toward the radiator??? The drum appears to be hanging up on the service brake shoes and linings.

Coyle,

Are you sure you mean you move the lever 'back'? Moving the service brake lever toward the back would mean toward the rear bumper of the car. When doing this, the brake shoes should not expand. They should retract fully??? This would mean the cam is turned 180 degrees as mentioned above???

See Bratton's rear brake assembly diagram on their web site. It also shows the correct orientation of the e-brake retraction spring when you get to that point.

Re: Rear brake woes
 

Could you have left and right mixed up?
Are the rollers touching the brake cam shaft like in the picture?
What size is the drum, if it’s new and hasn’t been turned it might be undersized.

Re: Rear brake woes
 

What all do I have to remove in order to turn that cam around?

Re: Rear brake woes
 

I deleted this response because it was incorrect. 'Got it backwards in my mind. No sense in spreading more false information here! :)
Marshall

Re: Rear brake woes
 

You have to spread the shoes apart to turn the cam around. Taking the springs off helps a lot but they are hard to put back on with the emergency shoes in place. The cam just pivots in the hole. If it is hard to turn then it may not be sliding well enough and should be removed to clean it up and to put a small amount of grease on it.

Regarding the adjustment. The screw is a right hand thread and unscrewing (counterclockwise) it from the back of the backing plate will make the adjustment retracted. If viewed from the shoe side of the backing plate then the direction would be clockwise. If this is confusing then just observe the shoes being retracted when turning the adjustment.

Re: Rear brake woes
 

Right you are, nkaminar. I was thinking backwards. I'll alter my post to reflect the right way.
Marshall

Re: Rear brake woes
 

One more question for nkaminar while I'm trying to figure out how to spread the shoes with the springs on. Do I need to remove the cam and flip it end for end, or just rotate it 180 degrees while it's still in the hole?

Re: Rear brake woes
 

Just rotate it in its holder....if it is backward :)

Re: Rear brake woes
 

I suggest you watch this YouTube video: "How to Stop on a Dime"

https://www.youtube.com/watch?v=3GFMJ7iiWiI

Re: Rear brake woes
 

I noticed you said you turned the adjuster (adjusting wedge) counter-clockwise to its stop. This does not assure the service brake shoes are fully retracted. Once you hit the stop, you need to turn it back slightly clockwise until you feel the adjusting shafts "click once" so that they are "seated" in the low spots on the adjusting wedge. This is especially true with newly lined brake shoes.

I'm not negating the possibility that the position of the cam is reversed, but the possibility of this is slim if the rebuilder sent you back the backing plates fully assembled. (If this were the case, they might have had an issue with properly centering the brake shoes). On the other hand, if the shoes are not properly retracted, the problem you have is VERY possible. Good Luck in your endeavors.

Re: Rear brake woes
 

First of all, let me say how much I appreciate the folks who've taken the time to try to help me with my problem. But I'm still stumped. I tried turning the adjusting wedge back to make sure it wasn't caught on one of the ridges, but that didn't make any difference.
The space between the brake shoes and the edge of the backing plate is about 3/4 of an inch all the way around, so it appears that the shoes are centered. When the lever is pulled forward, the shoes are closer together (further retracted) than they are when the lever is positioned toward the rear (pointed the way it should go). The rollers are seated fully on the cam, not riding up on one of the ridges. I can't find anything else to figure out what's wrong.


Please let me know if you have any other suggestions.

Re: Rear brake woes
 

Until recently, one of the rear axles on my car had a worn axle key way. Sometimes when I attempted to reinstall the hub and drum, the key would slide toward the backing plate and prevent the hub and drum from going all the way on. The key way is supposed to be a snug fit and not allow the key to do this.

You might try removing the axle key and test fit the hub and drum to see if it will go on all the way. The bevel at the end of the key goes face down to the axle and at the backing plate end of the key way.

Re: Rear brake woes
 

coyledad46

I tried to PM you, but you are not set-up to do them.
I will; try to help you if you would like.
Call me at 714-292-8660

Randy Gross

Re: Rear brake woes
 

Good thought on the keyway preventing the drum from going on fully, but it sounds like the shoes are still operating backwards. Pull the arm and they retract and he can get the drum on, then can not move the arm back upright ?
A great offer from one of the best brake guys out there, I would call Randy and see if he might be able to help straighten things out :)

Re: Rear brake woes
 

left and right backing plates switched or you have 2 of the same side perhaps

Re: Rear brake woes
 

Not sure if this is the best place to post this inquiry, but it relates to rear brake woes. I've had the rear brake shoes refurbished (not replaced) and replaced the prior the bonded lining to now woven brake linings. Does this automatically trigger the need to turn the drums? I have installed, realized I installed incorrectly, and reinstalled many of the rear brake parts including springs, etc. and believe I have it all correct. (learned a lot with all the mistakes, actually, but wasn't initially fun). However, when I attempt to test the hub fit - before buttoning everything down - it is either a very tight fit or not a good fit at all.

I'm curious, should the drum easily fit over the woven linings? I believe the rear right can fit over, though snug, but I can't even get the rear left to fit over the lip. Is this normal when going from bonded to woven lining?

Thanks for any help!

Re: Rear brake woes
 

Did you have the shoes arced to fit the drums?

Re: Rear brake woes
 

No. Because it is the same, original shoe (just cleaned/painted) I didn’t think that was necessary. Same drums too.

Re: Rear brake woes
 

This is an important step in brake repair always.

Re: Rear brake woes
 

I recently encountered a wallowed-out key in the left rear axle because someone had been running the hub loose on the axle to prevent if from going in too far and rubbing against the backing plate. BRILLIANT and so typical of the "repairs" I run across! There was a 0.013" gap alongside the key (see photo with feeler gauge), which doesn't sound like much, but it's enough to cause a loose key. That key is supposed to fit in the groove very tightly. Neither the original nor a repo key stayed in the groove. The hub would bind up when attempting to install it because the key kept coming out of its groove in the axle.
To narrow the groove, I supported the axle end over a floor jack with a body dolly between them. Then with a heavy hammer I beat on the edges of the groove along its length until they closed in enough to keep the key tight. It worked! The new key fit into the groove with light tapping and the brake drum slipped over the axle and key. All seems good once everything was back together again and the drum turns freely now.
Marshall

Re: Rear brake woes
 

I just found out the issue on how to get my hub to fit: I needed to fully seat the tightening brake adjustment wedge! Now it goes on just fine. Phew.