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[email protected] Samba Member
Joined: February 23, 2003 Posts: 11
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Posted: Mon Mar 24, 2003 5:34 pm Post subject: 72 Brake Servo |
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I recently put the front end of a 72 bus on my 70. On the brake servo, there is a vacuum line that runs back to the engine and the other line that disappears into the body. Not knowing what's in there, I just threaded a pipe fitting in there and stuck the hose to it.
Can you guess the problem? Oviously y engine is doing crazy things. Won't idle, or will idle but super high.
What is the purpose of that second line and what can I do about it?
Help me PLEASE!!!! |
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Karl Samba Member
Joined: January 29, 2001 Posts: 6170 Location: Coos Bay, Oregon
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Posted: Mon Mar 24, 2003 8:04 pm Post subject: 72 Brake Servo |
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UNPLUG IT!!!
That is the clean air side of the booster. It has to have atmospheric pressure on that side for the diaphragm to move. In a normal car, the clean air side is in the passenger compartment. On the bus, the booster is totally exposed to the elements. If the hose was not there, water would enter when you went thru a puddle. The hose goes up into the body cavity in the left dogleg and B pillar. |
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[email protected] Samba Member
Joined: February 23, 2003 Posts: 11
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Posted: Tue Mar 25, 2003 9:53 pm Post subject: 72 Brake Servo |
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I unplugged it, and the engine just dies. Just out of curiousity, I capped it and the engine runs fine, but now what about the booster? |
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Karl Samba Member
Joined: January 29, 2001 Posts: 6170 Location: Coos Bay, Oregon
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Posted: Tue Mar 25, 2003 10:48 pm Post subject: 72 Brake Servo |
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You only have the big vacuum line going to the nipple on the same side as the master cylinder, correct?
The nipple on the back side is open?
And with the back nipple open, the engine dies?
If yes, you have a bad booster. The diaphragm is blown.
There was a NOS booster on ebarf about a week ago but I cannot find it.
There is a place in Texas that rebuilds them. |
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breadloafdeluxe Samba Member
Joined: February 12, 2002 Posts: 418 Location: Birthplace o Tx. Brazoria Co.
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Posted: Thu Mar 27, 2003 6:09 am Post subject: 72 Brake Servo |
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Of all the parts the booster is one of the few where the rebuilt part may be better than NOS,something to do with the rubber diaphram and 30+yrs on a shelf. |
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[email protected] Samba Member
Joined: February 23, 2003 Posts: 11
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Posted: Sat Mar 29, 2003 10:46 am Post subject: 72 Brake Servo |
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Okay, thanks much. There's one more thing I want to try before I get a new booster. I'm able to blow both ways through the check valve, so I'm replacing it and will see if that works. |
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