Soft brakes after pad replacement


#1

The front pads were starting to get a bit worn on my 94 Dakota so I replaced them – pulled off the old pads, compressed the piston with a C clamp, put on the new pads and put the calipers back on. Now the brakes feel soft and jumping on the brake pedal won’t lock the brakes. I think only the rear brakes are working. Help?


#2

[b]Does this vehicle have ABS?

Tester[/b]


#3

air, bleed them


#4

No ABS.


#5

I thought about that but the line was never open and the reservoir is full. Could air get into the line some other way?


#6

[b]If you didn’t open the bleeders on the calipers before pushing the pistons in, you may sent cruddy brake fluid back up into the master cylinder. And the crud in that brake fluid is now preventing the cup seal in the master cylinder from sealing properly. Thereby not allowing hydraulic pressure for the front brakes.

First try bleeding the brake system until all that comes out is clean brake fluid. If this doesn’t work, then one would have to assume that something happened to the cup seal in the master cylinder when the brake fluid was forced into the master cylinder when the pistons were compressed.

Tester[/b]


#7

While someone presses the brake pedal, and the bleed screw is loose, if a nice pee stream of brake fluid doesn’t come out, there is an obstruction in the brake hose. Replace the brake hoses. If the bleed streams are OK, tighten the bleed screws and have someone press the brake pedal firmly while you observe the brake hoses. If they appear to SWELL, they should be replaced.


#8

Adding to that idea, suction (using a hand pump, turkey baster, etc.) the old brake fluid out of the brake master cylinder reservoirs. Fill with fresh brake fluid, then, bleed at the brake calipers.


#9

You should bleed the brakes as part of your normal pad replacement, but the problem could be with the caliper guides and pins. The calipers may not be floating properly.

If the rotors had a lot of grooves in them, it may take awhile for the new pads to bed themselves, that will take care of itself in time, but I’d make sure the calipers are floating first, them bleed the whole brake system, front and rear, even though you didn’t replace the rear shoes.