Bad brake booster check valve

RGG · Post by **RGG** » 26 Jun 2010, 19:55

Would a bad brake booster check valve
cause the vacuum booster pump to overheat and whine ?

clarkandrew45 · Post by **clarkandrew45** » 12 Jan 2011, 18:12

RGG wrote:Would a bad brake booster check valve
cause the vacuum booster pump to overheat and whine ?

Based on my opinion, Yes. as per some article i have read.

Post by **jimmy57** » 12 Jan 2011, 23:38

The vacuum switch that turns pump on is a more likely culprit. The check valve is there to hold vacuum when the vacuum source gets low. A defective booster whose regulator/vent valve is faulty would cause a vacuum leak and a properly functioning pump and vac switch would run all the time.
Easy test. pull the hose off booster check valve and plug it and see if the pump stops. If yes, then booster. If no then leaks in line from pump or the other check valve in the plumbing tying the vac pump to the intake manifold vac line need to be ruled out and then the pump or vacuum switch needs to be checked. I can't remember if the vaccum switch on the s/v40 models is part of the pump or in the line to the pump.