New motor installed, very low vacuum???
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Drifting
Joined: Feb 2002
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From: Schererville Indiana
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New motor installed, very low vacuum???
I just installed a new LPE built ASA motor. Cam specs 23x .525 110 lsa. I took it for the first ride locally and thought my brakes were not bled well enough. I went through the brake system and it is fine. When I remove the vacuum line from the brake booster there is very little vacuum. The pedal feels very hard (like there is air in the system.) We raced it today but really had to "muscle" the pedal. What can I do to get more vacuum.
Le Mans Master
Joined: Oct 2003
Posts: 6,126
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From: Streamwood illinois
id put a gauge on it to see what vacuum is but i thought the booster had a 1 way check valve that would store vacuum in the booster. I dont think your can is big enough to warranty a vacuum resevoir so maybe you have a vacuum leak. Id get a gauge on it and checka ll hoses etc.
Dave
Dave
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Drifting
Joined: Feb 2002
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From: Schererville Indiana
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re
The booster does have a check valve. When I remove the booster line it has almost nothing compared to a stock motor. This line comes right off the manifold so the vacuum should be very good.
Racer
Joined: May 2001
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From: Bryn Mawr PA
This exact problem surfaced with recent R&R on my ride. Had to replace the booster to cure it. Tech had no idea why it occured but problem was resolved by new booster.
Have no idea why.....................
Have no idea why.....................
Thread Starter
Drifting
Joined: Feb 2002
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From: Schererville Indiana
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?
Originally Posted by Jack Behrle
This exact problem surfaced with recent R&R on my ride. Had to replace the booster to cure it. Tech had no idea why it occured but problem was resolved by new booster.
Have no idea why.....................
Have no idea why.....................
Thread Starter
Drifting
Joined: Feb 2002
Posts: 1,422
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From: Schererville Indiana
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update
Update, I found a plug inside the manifold nipple that goes to the booster hose. It had a external plug which I removed but it had one threaded inside the hole too. 
