1997 2 wheel drive, rear abs only.

Had a little time, so I thought I would replace the rear brake shoes and drums. Never opened up the hydraulic system so I don't think the problem would be air in the lines or MC. Did not have any trouble with the brakes prior to replacement. It also has the chevy wheel cylinders done a few years ago.

After all done and adjusted the brake pedal feels spongy and the ABS and brake light go on when applying brakes until "pumped up" and then the pedal firms up and lights goes off. After a minute or two the pedal is spongy again and braking power is less, and it needs to be pumped up to brake "normal".

The only thing done to the rear brakes was new drums, new shoes, new hardware. Did not bleed and the system has no leaks.

So whats the deal? Odd that everything was fine and now a problem. I double and triple checked my installation, and emergency brakes work fine. I do have a full load of firewood in the bed of the truck, does this have anything to do with it?

Any ideas? Thanks in advance, KD

 

Light may have come on by allowing the master to run too low on fluid while you were bleeding.
Some hard codes like brakes require disconnecting the batteries to make the lights go off even after the problem is corrected.
Spongy brake is symptom of air in the lines, bleed again.

 

Infidel, thanks, but I never opened up the hydraulics. Never did any bleeding except 2 years ago when replaced wheel cylinders.

The rear brakes I just replaced today-I never opened up the system, just did brakes and hardware-no bleeding.

It's got me kind of puzzled. Thanks, KD

 

This might be a dumb question, but did you double-check that the wheel cylinder apply pins are engaged properly with the shoes? It's easy to miss one and have it shoot out behind the shoe when you step on the brake.

 

Torquefan, thanks, yes, I double checked. I'm pretty sure your talking about the pins that have a "H" type slot that fits in the shoes slot and the other end goes into the piston? I have had the drums off 3 times now, and I have checked this.

Besides, if that happened, I imagine I would have brake fluid leaking out the wheel cylinder and eventually on the side of the tire and floor?

I am sure the slots are in the groove. I am gravity bleeding the system right now and have the batteries disconnected, so who knows if that will help. KD

 

Well it seems fixed.

Out of desperation or frustration, I disconnected the batteries, sucked out most of the old fluid in the master cylinder reservoir, added new fluid, and gravity bleed the rear brakes. I also adjusted the brake adjusters a little tighter than I normally do. I could still turn the wheels by hand, but a little more drag than I usually do.

Braking power is back, even better than before the repair. No more ABS light, no more brake light, no more spongy feel.

Not sure what I did wrong initially, or what really fixed it. The funny thing is I never opened the hydraulics portion of the brake system. Just did shoes, drums, and hardware.

Oh well at least I got to listen to the Detroit Lions go 0-16 while messing with the truck. Thanks for the help. KD

 

I know this is basic, but did you recheck the brake adjustment. Ocassionally I've had the shoes "settle" in and found the adjustment was off enough to cause a spongy pedal.