brake problem

[G Winter]

I have a 1989 Riv, 162k on it 4 wheel disk brakes . The brake pedel will give some brake at the beginning , then get soft and drop near the floor and then give me some brake again. I can pump them up a little but still not very good brakes.When this happens I get a slight pull to the left. At times they work just fine. Need opinion on this. Is it the master cyl. I have never had one come and go like this one, so I was wondering if a calipers would cause this.
thank you .
Glenn

 

[wishuwerehere82]

Glenn,

My mother has a '90 Riv. and I never have been happy with the anti-lock brakes on that car. They are marginal at best even when properly operating. I have to really stand on the pedal to get that thing stopped, and it has always been like that.
Partly, the anti-lock system pressurizes the cylinder and is a one-shot deal to operate the ABS pulses. Use it twice within a few seconds and isn't there the second time. I know, I tried it in a snowstorm to verify operation and then slammed into a hospital curbing a few seconds later when they didn't work.
I think it has something to do with a sticky check valve on the cylinder refill circuit. Sometimes it works OK, and sometimes you have to stand on the pedal.

 

[G Winter]

thanks for the reply. Mine does not have the antilock brakes. You are right,the early model antilock brakes are problamatic.

 

[wishuwerehere82]

Oh that's different!
Sounds like you may have a hose that has broken the nylon webbing in it, causing a bubble in the rubber brake line.
That would cause all of the calipers to engage except the one with the bubble. By bubble I mean a ballooning of the line itself, not an air bubble. Have someone stand on the brakes for you while you look at the rubber lines that go to the wheels. If you see some swelling in the line, that's the problem.

Other causes could be a bad master cylinder or air in the brake lines. Although a bad cylinder itself would not cause pulling to one side.

 

[G Winter]

If I understand the brake system on these cars. The left front and right rear and right front a left rear work together respectivly on the two halves of the master cyl. If one half was bad wouldn't that make it pull just slightly ?

 

[G Winter]

I replaced the master cyl. and the brakes work perfectly now.

 

[wishuwerehere82]

That's good that that's all that it was.

The front left caliper on my '82 is leaking fluid out on the wheel and it's pulling to the right now. Swell!

 

[G Winter]

Are you sure it isn't the line? Is that a situation where you should buy a pair ? I hope it is many many miles before I have that problem, those calipers can't be cheap. Rebuilding a calipers isn't all that easy. Been there done that, many yrs ago. Ever notice how when you think you just got things all squared away something else goes wrong? :ugh

 

[wishuwerehere82]

Those (2)calipers are only a year old and 1 is leaking already.

I'll see if Raybestos will give me a credit for them.

 

[G Winter]

the place you bought them usually handles that for you. May depend on how good they are.