Moaning sound from either new Vac Booster or new master (1 Viewer)

Joined
Feb 16, 2011
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822
Location
San Diego, CA
Just wrapping up a disc brake swap on my 40. Everything is new Vac Booster, Master, lines, calipers etc.

  1. Engine hasn't ben started since new swap has been completed, so nothing has had vacuum applied
  2. Booster has a new check valve, and hose to the manifold
  3. When I press the pedal, I hear the moaning and feel vibration in the vac booster hose.
  4. Thought maybe bellows were causing it, but I pulled them forward onto the rod, to they arent contracting or expanding.
Any thoughts? Booster and MC are from City Racer, and the noise happens everytime I press the pedal. I can tell I still have some bleeding to do but the system is close.
 

1911

chupacabra
Joined
Aug 11, 2006
Messages
6,474
Location
Parker County, Texas
Back in the old days we would have said your booster was possessed or haunted, but now we know it is an imbalance of bodily humors caused by a toad or a small dwarf living in the booster.

- Theodoric of York
 
Joined
Feb 16, 2011
Messages
822
Location
San Diego, CA
FWIW, heres a video of the noise.


I also hooked a vac pump on it and it held vacuum for several minutes. I also disconnected the line into the manifold and blew into it, air blew freely into the check valve. I also made sure there were no obstructions on the manifold side either.

This was the expensive booster that @Racer65 sells so I am surprised there is an issue, and unsure of how much of a pain it will be to return
 
Joined
Feb 16, 2011
Messages
822
Location
San Diego, CA
I pulled the check valve and there was some wierd black sludge coming our of the back of it. I cleaned all the out and lighly blew some air threw it. The sound lessened considerably so I am guessing that is the issue. Hopefully I can get a hold of cityracer when they open back up and see if I can get a replacement check valve from him.
 
Joined
Feb 16, 2011
Messages
822
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San Diego, CA
Just wanted to update since this was weird. Definitely ended up being the check valve. I pulled it and there was some kind of lubricant/grease on the diaphram side. I cleaned it out, blew through it and more came out the manifold side and it still made that moaning sound.

City Racer reached out via email and he shipped me out a new check valve which solved the problem. Thanks for the help @Racer65
 

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