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I don't think that sounds right. My intake vacuum is 20 in. at idle, and I don't think your car would run well at 2 in. Could there be a problem with your gauge? I know your brakes are the problem, but 2 in. is just too low.
If you really are running 2 in. of intake vacuum, you have an engine problem or a large intake leak. Sorry. Engine compression OK?
Good luck,
Dave
I don't think that sounds right. My intake vacuum is 20 in. at idle, and I don't think your car would run well at 2 in. Could there be a problem with your gauge? I know your brakes are the problem, but 2 in. is just too low.
If you really are running 2 in. of intake vacuum, you have an engine problem or a large intake leak. Sorry. Engine compression OK?
Good luck,
Dave
sorry your correct 20in at the intake 10 at the nipple comming off the booster check valve, 5 at the test port. Engine is fine runs awesome didn't have this issue until my master cylinder went out, replaced the master ,during the removal of the master cylinder removed the hose going good into the booster heard the vacuum hiss out, completed the master cylinder install, and the brakes have been stiff ever since, thought the booster was bad, so I replaced it, pedal still stiff sent booster back for exchange and the same problem, I have been turning wrenches almost my entire adult life, I know I'm over thinking the issue, boy does my brain hurt.lol.
OK, that's better. The brake booster only has one connection with a small side nipple. Cap the nipple and with a suitable adapter connect a Mityvac hand vacuum pump to the booster. Pump the Mityvac and see if the booster will hold 20 in of vacuum. If not, you have a bad booster. Even two in a row is not impossible. It is also possible that the brake booster check valve/connection is leaking at its insertion point. but at least you have narrowed down your vacuum loss.
Good luck,
Dave
OK, that's better. The brake booster only has one connection with a small side nipple. Cap the nipple and with a suitable adapter connect a Mityvac hand vacuum pump to the booster. Pump the Mityvac and see if the booster will hold 20 in of vacuum. If not, you have a bad booster. Even two in a row is not impossible. It is also possible that the brake booster check valve/connection is leaking at its insertion point. but at least you have narrowed down your vacuum loss.
Good luck,
Dave
Ok that was the advice I needed used my snap on vacuum tester attached to the booster won't hold any vacuum , so the booster is not holding any boost at all, that socks but now I know so here I go again thanks for the AWESOME HELP OWE YOU A BEER, CHEERS
any chance you installed the check valve to the booster backwards?
Its a good idea to check and see if you can pull a vacuum on the new booster with your hand suction tool, if not then you might have scratched the MC seating area or not installed the square O ring that seals the MC to the booster.
NOTE use DC111 on the MC O ring and on the reservoir rubber grommets to prevent the MC from corroding
if you pull the valve out of the booster then run the engine you should feel a suction from the end of the check valve.
NOTE take the vacuum source from the front fuel damper,
using the small check valve port will not show the current suction,
as your reading after the venturi so this will be higher than the actual intake vacuum
any chance you installed the check valve to the booster backwards?
Its a good idea to check and see if you can pull a vacuum on the new booster with your hand suction tool, if not then you might have scratched the MC seating area or not installed the square O ring that seals the MC to the booster.
NOTE use DC111 on the MC O ring and on the reservoir rubber grommets to prevent the MC from corroding
if you pull the valve out of the booster then run the engine you should feel a suction from the end of the check valve.
NOTE take the vacuum source from the front fuel damper,
using the small check valve port will not show the current suction,
as your reading after the venturi so this will be higher than the actual intake vacuum
how do you install the one way check valve going into the booster backwards, anyway, removed the grommet in the booster hooked up vacuum gauge and pumped for all I was worth , gauge never moved, so if I try and pull straight from the booster , there ain't no vacuum. Start the car put finger over hose going into the booster there is lots of suction, so I believe my booster is no good., how would a master cylinder cause a stiff pedal a soft pedal a spongy pedal never a hard pedal.
did you put the new square O ring into the back of the new MC and use DC111
If you post pictures of what you have it will make the answers better as we are all guessing what you have done
did you put the new square O ring into the back of the new MC and use DC111
If you post pictures of what you have it will make the answers better as we are all guessing what you have done
sorry for the delay , broke my foot, anyway the issue was 2 fold diaphragm, torn or cracked in the booster, second venturi was leaking ,so I'm awaiting parts new booster, won't work on the car until my foot heals .
Dropped a.c. compressor, broke big toe right foot,you have brought up a food point about the seal for the master, I honestly can't remember if I put that seal back. Will let you know.
Ok so I believe mr,merlin has led me into the light, replacement booster arrived, so despite the broken toe and the docs orders, I began the removal off the old booster, ànd I remove the master and there is no gasket, at the base,lol I think that's where the vacuum is leaking. Anyway it's dark now and my new safety shoe is melting, see pics lol..
The latest in your a dumb *** fashion, lol.🤕🤕
sorry to hear about your foot.
I hope it heals fast
How did you break it?
By kicking the old booster?
Thanks for the insight into the master cylinder, the seal was missing on the master cylinder, replaced with new base gasket and another booster and Allis well, thanks again.
06-03-2017, 08:44 AM
