Power Brake Booster

[acman60]

I am changing the brake proportioning valve and the master cylinder and all the brake line.How do i know if the power brake booster needs to be replaced.It is 30 years old but i do not know how to tell if it bad.

 

[74bigblock]

I am changing the brake proportioning valve and the master cylinder and all the brake line.How do i know if the power brake booster needs to be replaced.It is 30 years old but i do not know how to tell if it bad.

If the brake pedal gets hard after leaving the car for an hour or overnight it means it is leaking pressure and is on it's way out.

If the brakes are hard to apply while driving period... it's already gone.

** Assuming in both cases above you checked for good vaccum and no leaks in hose!

For $60 you can replace it anyway and not worry about it.

** Just make sure your new master fits on your new or old booster before filling the master and installing. If you by a new booster, I would also make sure the nuts that hold the new booser in fit inside the small area above the brake pedal before installing completely. I ended up having to go through 3 sets of each before they got it right (Muskeegon Brake). DO NOT USE THEM! THEY SUK.

Good luck.

Dave

 

[Vettehead Mikey]

Loss of vacuum with the engine shut down is usually a bad check valve, not the booster itself.