Any way to troubleshoot brake booster?

[chirp]

I just picked up an 83 911, it has a 3.2 swapped into it. The brake pedal is very hard to push.

I pulled off the vacuum hose at the booster and it is sucking so it's hooked up.

Any other way to trouble shoot before I start throwing parts at it?


Thanks!!

[boyt911sc]

Connect a vacuum pump to the brake booster hose and see how much vacuum it holds steadily for 5 seconds.

Tony

[chirp]

See how much vacuum the booster holds?

Thanks

[boyt911sc]

Originally Posted by chirp

See how much vacuum the booster holds?

Thanks

chirp,

Just for the heck of practice, check the vacuum reading going to the brake booster while the engine is running. Let say you obtained 22" Hg reading. Reconnect the brake vacuum hose with the pressure gauge connected at T-connection and start the engine. You should obtain the same reading of 22" Hg if the brake booster is not leaking. The earlier test I suggested is much easier and easy to performed. If the brake booster could hold the pressure unchanged for a long time, it is not leaking.

Tony

[chirp]

Copy. I'll check it out.

Thanks for the help.

[porwolf]

I read about it here and tried a simple trick: Step on the brake with the engine off. Start the engine and feel the brake pedal moving forward. That means the booster is working.