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spongy brake pedal after shoe repl

I replaced the rear brake shoes on both sides, replaced both wheel cylinders and bled both rear brakes (or at least I thought I bled them good enough). Problem is I have alot of free play in the brake pedal. It has to get almost all the way to the floor until I feel the brakes kicking in.

I take it the star wheel adjusters need to be rotated to push out the shoes some on each side. I had them turned all the way in, so they were about their shortest distance.

Is it necessary to use a brake spoon and screwdriver through the back hole or can I just adjust and put the drum back on, adjust and put the drum back on until I get the right setting? Guess I should have cranked the car and felt for the correct feel of the bake pedal before I claimed the job was done.

Another thing I learned during the brake job is how things can go so bad after lots of miles. For example, one of my wheel cylinders had a frozen piston. The other wheel cylinder worked but it didn't look so good. One of the star wheel adjusters had corroded and welded itself to the shaft its supposed to rotate on so it wouldn't let the star wheel rotate at all. And of course, the condition of the brake shoes themselves (lining fell of one of the shoes and broke up inside the drum, causing some grinding and bumping noises which is what got my attention to begin with!).

Reply to
roger
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I hope you replaced all that frozen and corroded stuff.

If you don't want to crawl back under there with the spoon, you can simply drive the car forward and backward about 10 feet and stop a dozen (or a couple dozen) times and see if the pedal starts firming up (the star wheel should move a little bit on each stop when going backward. That will tell you if the automatic adjusters are actually working and tighten them up for you. If it doesn't start to get better after doing that, you probably needed to replace a couple more parts, or the adjusters weren't reassembled quite right.

This is all assuming you are working on old American iron. Some other cars engage the automatic adjusters when the parking brake is applied. So if driving it back and forth and applying the main brakes doesn't help, you might also try doing it with the parking brake.

Reply to
E. Meyer

Yep, that about diagnoses the problem right there.

Yes. Crank 'em down until you can just hear them dragging when you turn that wheel, then back off slightly. That'll get you in the ballpark. Now find yourself an empty parking lot or other clear place. Get a feel for where the brake is starting to bite, then roll back and forth several times. Try to hit about 15 MPH going backwards, and mash the brake pretty firmly when stopping each run. Half a dozen times should work the auto-adjusters enough to put things where they're supposed to be. If the pedal is still spongy/long throw, do a few more fairly hard stops from about 15 mph in reverse. If that doesn't clear the problem, it's time to bleed the brakes again.

You'll never get them set right that way. OK, pardon me - you might be able to get them set correctly, but you'll never get the drum back on when the adjustment is correct. To get it to go on, you'll have to take it out of adjustment, which puts you right back at going in through the backplate with a brake spoon/screwdriver to put it back in after you get the drum back on.

Reply to
Don Bruder

It's your adjuster likely.

You have to get the adjuster star wheel really close to tight before the self adjuster will start working on most vehicles.

A friend did like you recently and we had to take it all apart again. Because he didn't set it up, when he used the brakes parts fell out of place. One star wheel feel out and the adjuster cable on the other side fell off it's track because it was so loose.

You 'might' be able to adjust it close enough with the drum off. It depends on how much of a ridge is on the drum.

Once you have the star wheels close, you need to find out how the self adjuster works. Some work when you hit the brakes in reverse after a forward stop and some use the emergency brake.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

roger wrote:

Reply to
Mike Romain

You have gotten some good counsel from the other posters here, and I would only add that the adjusters for the left and right wheels are totally different.

If you did the wheel one at a time, then you would not have made a mistake.

Some people have had the misfortune to get the adjusters mixed up, and they will never work that way.

Reply to
Larry Smith

.....or can I just adjust and put the drum back on, adjust and put the drum back

That's the way I do the initial adjustment. Adjust some, push the brake pedal to "re-center" the shoe assembly, repeat a couple times until you can just barely slide the drum on. MAKE SURE you put the drum back on before pushing the pedal!

If you didn't replace the Master Cylinder, you can often damage the piston seals when pushing the pedal all the way to the floor. The piston starts "working" in areas of the bore that haven't been used in a long time. Sometimes these areas are pitted and will "eat" the piston seal.

I'd also recommend "flushing the entire system. You have it halfway flushed already. Get the rest of the old, cruddy, water laden fluid out of there.

Reply to
bkapaun

"Don Bruder" wrote

Hmmmm....that's funny, this is the way that I do most rear brake adjustments these days. Many of the late model GM vehicles do not have holes in the backing plates. And anyone who replaces the brake shoes without resurfacing the drum, or at least getting rid of the ridge, deserves to be backing up in the parking lot for a bunch of panic stops. With a machined drum, you can set the adjustment by just sliding the drum on and off and checking the clearance.

Ian

Reply to
shiden_Kai

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