brake problem

[dallastx75208]

[gordr]

I believe there is a bleed screw on the hydrovac. I know Stude truck hydrovacs have two bleed screws, and on my 2R17A, I had to bleed both screws to get it to work.

Your car should have a residual pressure valve; they were used on all drum brake cars for years. It's built into the master cylinder, forming the "foot" on the base of the internal spring.

Usually, if you get a good hard pedal after one pump, the problem is brake adjustment, not air in the lines. Air gives you a spongy pedal.

Most likely, some of the shoes are simply having to travel too far to reach the drums. I'd suggest that you adjust each wheel until the brakes are tight enough that it won't turn by hand, then back off until it just releases. Don't back off to the point that the shoes don't touch at all.

Gord Richmond, within Weasel range of the Alberta Badlands

[dallastx75208]

Adjusting did it. The back shoes were way off. Thanks a lot for the information.

quote:Originally posted by gordr

I believe there is a bleed screw on the hydrovac. I know Stude truck hydrovacs have two bleed screws, and on my 2R17A, I had to bleed both screws to get it to work.

Your car should have a residual pressure valve; they were used on all drum brake cars for years. It's built into the master cylinder, forming the "foot" on the base of the internal spring.

Usually, if you get a good hard pedal after one pump, the problem is brake adjustment, not air in the lines. Air gives you a spongy pedal.

Most likely, some of the shoes are simply having to travel too far to reach the drums. I'd suggest that you adjust each wheel until the brakes are tight enough that it won't turn by hand, then back off until it just releases. Don't back off to the point that the shoes don't touch at all.

Gord Richmond, within Weasel range of the Alberta Badlands