Stuck Brake Booster?

[OldBlue82]

So Im a little stumped... finally got my LS swapped Monte running and driving last week. Brakes worked well at the time. Today I go to move the car so I can get it ready for the exhaust install when I went to step on tthe brakes I quickly realized that I had no power assist to the brakes. So first thing I check is to see if there is a vacuum leak. the vacuum to the booster is at around 15-16 at 1000rpm. The car has a fairly radical cam in it. The booster is used but not seem to be leaking. The one way valve is working.... Just puzzles me since the car was braking fine when I parked it but now theres no assist and I have not changed a thing other than a leaking heater core. Could the diaphragm have stuck in the booster? Just seems odd.

 

[pontiacgp]

is the pedal hard or soft?

 

[OldBlue82]

is the pedal hard or soft?

The Pedal is hard. Have to really stand on it to stop the car

 

[pontiacgp]

if you pull the vacuum line off the booster can you hear the air rush?

 

[Bonnewagon]

You may need a vacuum reservoir can. Summit and others sell them cheap enough.

 

[OldBlue82]

shouldnt need a reservoir can, as a said it was braking fine before i parked it. I did pull the hose of and I have vacuum there (15-16in). I did notice that when pulled the hose off after I had just shut the car off and I heard air sucking in. One way valve is working.

 

[pontiacgp]

if you have enough vacuum and the pedal is hard then it sounds like a bad booster