Brake troubleshooting help needed (1 Viewer)

Joined
Sep 17, 2010
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98
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P-Cola, FL
A week or so ago I noticed that the brakes required a pump or three before they started working, checked the obvious things and found one of my wheel cylinders was leaking. I replaced both wheel cylinders on my pass side, and replaced the shoes on both sides and bled the rear brakes. I started on the pass side, then the driver's side, and then back to the pass side.

When I attempted to adjust the brakes, the adjusters went all the way to the stops and I am pretty sure the shoes weren't hitting the drums like the manual calls for... Turned the adjusting nut away from the axle. Anyway, I drove it around the block and they are still a little spongy and definitely are not grabbing like they should.

I'm not a huge fan of troubleshooting by swapping parts, but I'm thinking the drums may be worn beyond limits, an issue with the master, air still in the lines, or air in the front circuit. I'm doing the fronts next weekend when I've got a little more time. Input is appreciated. btw 1978 fj40.
 
Joined
Sep 17, 2010
Messages
98
Location
P-Cola, FL
I checked the booster IAW the test on SOR's website... Seems to be ok.

I installed the wheel cylinders the same way they came off. As you look at the left rear brake, the rear cylinder's adjustment knob is on the bottom, and the front cylinder's know is on the top. I rotated the the adjustment knobs so they turned away from the axle, but couldn't get them to engage the drums. I don't have them upside down do I?
 
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Sep 14, 2009
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North and South of Mason Dixon
I doubt that it is the drums being worn beyond limits. There is a lot of adjustment in the cylinders and you have new shoes. How did you adjust the brakes? Did you tighten them until you couldn't turn the wheel and then back off? If you turned them until they hit the stop and the wheel still turned, I suspect that you may have used the wrong cylinders or installed them in the wrong place. Try adjusting them the other direction and see if you can get the wheel to lock up. Or pull the drums and look at how the shoes move when you turn the adjusters.

I would recommend NOT messing around with the fronts until you figure out the rears. Your fronts are disks on a US 78, right?
 
Joined
Sep 17, 2010
Messages
98
Location
P-Cola, FL
Yep, disks up front. The wheel cylinders I used are centric p/n 13444720 and 13444718. Got 'me from rock auto, and they were identical to what I pulled off. The shoes were the same as the old ones. The thing is, I couldn't adjust the shoes out the engage the drums on either wheel. I really hope I just didn't turn them the wrong way.
 

JohnnyC

Long ago TLCA# 2231
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Jun 17, 2005
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UpState Ny, Wells Me
I'm thinking you turned them the wrong way

There is ALOT of adjustment to them

Adjust with tire on

If your still not getting it to drag on the drum... Take a pic... Maybe we can see what's a miss
 

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