Brake Pedal Does Not Fully Return

[ggrant5150]

I have an 85 Ranger 2WD. I have been having problems with the brakes not fully releasing. At first I thought I had a parking brake problem but that checked out OK. Eventually I realized that the brake pedal was not coming all the way back up after being pressed. It was only about 3/4 of the way back up. If I put my foot under it and pull it up, the brakes release and everything is OK, however, I hear a hissing sound near the brake pedal. If I keep doing this, after a few hours, the pedal starts coming up all the way and I no longer have to help it. Does anyone have any ideas?

Thanks!

 

[High Desert Ranger]

Power Brake Booster

 

[MAKG]

I agree that's the hiss, but I don't see how it can cause a return problem.

Given that working it seems to make a difference, I'd suspect the master cylinder is binding.

 

[High Desert Ranger]

Yes. I'd also suspect the master cylinder, and would probably replace them both together.

 

[ggrant5150]

It turns out the booster was full of rust! I went ahead and replaced the master cylinder too and bled the whole system while I was at it. Now if I can just fix my emissions nightmare I will be good to go.

Thanks guys!