How to check a brake booster.

[Zak's Z]

Hey guys, most of the snow is gone and it's time for me to get back to work putting the Z together. I have searched the forums and still can't find out exactly how to check a brake booster thats already off the car. I have the one from my car, and also have another one that I got awhile ago in a parts lot. I'd like to check them both to see which one I should use.

I read this from a thread on the reaction disk:

Remove the master cylinder and alloy plate from the booster.

You will see the rod, seal retaining clip and seal.

Remove the retainer carefully leaving the seal in place for now.

Once you have the retainer out carefully pull the rod out untill it hits the back of the seal and use the rod to remove the seal at

the same time as you remove the rod. There shouldn't be too much force required to do this.

If the disc is not stuck to the back of the rod , or you can't see it in the recess in the diaphragm, then you have found your problem.

If the disc is there then you have discounted that as the problem and we're back to square one.

Anyone know step by step what I should be checking to see if they work properly?

Thanks,

Edited March 14, 2009 by Zak's Z

[beezee]

Zak, The FSM tells you how to check on the car with a vacuum gauge attached between the check valve and master-vac ,run the engine then shut off and maintain 20" Hg for 15 seconds no less than 1 "Hg pressure drop. Test 2 run the engine and shut off and apply brake pressure,should drop no more than 1"Hg. I have vacuum pump and gauges , we could simulate and test off the car. Rick

[Zak's Z]

Thanks Beezee, but my brake booster is on my bench and theres nothing on my car except wheels! Any other ideas for when the booster is out??

Thanks again,

[beezee]

Zak, I have a portable vacuum pump that could be connected to the booster off the car to simulate engine vacuum, just a matter of barb hose fittings and a vacuum gauge.