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Old 01-13-2003, 03:01 PM   #1
Low68
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More vacuum leak questions

Hey everybody...If you remember, I asked about a vacuum leak that I had. It was suggested that I replace the vacuum check valve and the gasket. I did that, but it didn't make any difference. Is there any other gaskets that can be the cause of that? Does it sound like my booster is shot? I want to try replacing any possible gaskets before having to buy a new one. Thanks for the help.
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Old 01-13-2003, 05:40 PM   #2
72MARIO
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I think it could be the booster they should be fairly cheep Buy a new one .
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Old 01-13-2003, 05:59 PM   #3
lukecp
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Take the booster vaccum hose off, and plug it or pinch it shut. Drive the truck w/o power brakes (just don't go very fast) and see if you still have a vaccum leak. Another way to check the booster is to get in the truck with the engine off, pump the brake pedal 5 or 6 times until it gets really stiff. Then put your foot firmly on the brakes, and start the engine. When the engine fires the brake pedal should sink in about an inch or two if the booster is working good.
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Old 01-13-2003, 06:19 PM   #4
Low68
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Thanks for the help. Other suggestions are welcome also. I want to get this fixed. Thanks
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Old 01-13-2003, 06:56 PM   #5
ChevLoRay
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Hydro-Vac's do go bad. That is the vacuum booster that you are citing. With the engine running, does it run rougher when you press the brake pedal down? Do you hear a "Hiss"? If so, the odds are that the diaphragm in the booster is leaking. You can't fix it. You will have to use it as a core to get a replacement. Good luck.
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Old 01-14-2003, 12:43 AM   #6
hecticblasts
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vac. leak

If you are running an automatic with a vaccum modulator check the connection at the fitting and at the modulator for dry rot.HF
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