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Old 12-04-2007, 08:36 PM   #1
bob1967
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power brake vaccuum line

I just put a disc brake conversion on my truck and power brakes. Is it better to run the vaccuum off the intake or the carb. And have any of you ever had a master cylinder drain the back resevior into the front and over flow the front resevior. This has been a head ache of a project nothing has gone right . Any help is greatly appreciated. Thanks
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Old 12-04-2007, 09:22 PM   #2
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Re: power brake vaccuum line

I'm not positive but I would say you should connect to a vacuum source on the intake.
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Old 12-04-2007, 09:26 PM   #3
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Re: power brake vaccuum line

Manifold vacuum. Carb has little or no vac at idle.
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Old 12-04-2007, 09:36 PM   #4
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Re: power brake vaccuum line

When i did mine i took a plug out right behind carb (V8). Also I had more problems converting to disc brakes it was a Pain. But I am done now.
About the resorvoir problem did you bleed the MC before you hooked up the lines. Good Luck
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Old 12-05-2007, 06:58 AM   #5
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Re: power brake vaccuum line

Thanks for the responses. Husker we bled the master, proportioning valve and the brakes, still pushes out. we thought after the proportioning valve we had it fixed started the truck and it overflowed and the brake pedal went down and didn't come back up. Think now it is headed to the shop so they can get it done.
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Old 12-05-2007, 07:15 AM   #6
truckdude239
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Re: power brake vaccuum line

its bad master cylider it is leaking internally
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Old 12-05-2007, 07:19 AM   #7
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Re: power brake vaccuum line

Fellas, hook your vacuum connection to the carb. That's where the general connected them from the factory. That way you get full manifold vacuum from a nice big port.
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Old 12-05-2007, 12:40 PM   #8
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Re: power brake vaccuum line

The vacuum can be hooked to the large port in the rear of the carb. It is beneath the throttle plate, so it is manifold vacuum. It can also be hooked to the manifold port where the auto trans modulator is hooked by changing the fitting. Either place is acceptable. As far as the master cylinder, replace it if it is transferring fluid between reservoirs.
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Old 12-05-2007, 01:56 PM   #9
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Re: power brake vaccuum line

They are hooked to the bottom rear of the carb from the factory! but some carb bases do not have the tapped boss on the rear.

Hooking to the manifold will work fine too though.
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