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Old 04-03-2004, 11:17 PM   #1
rage'nrat638
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Booster Vacuum Question

I HAVE PUT TWO (2) BOOSTERS ON MY TRUCK BECAUSE THEY ARE NOT HOLDING VACUUM.....

LEAVE IT SIT FOR A DAY NO VACUUM.....
YES IT'S GOT NEW CHECK VALVES.....TWO INLINE AND YES I GREASED THE RUBBER GROMIT TO MAKE SURE IT SEALS....

SO...ARE THESE THINGS SUPPOSED TO HOLD VACUUM....
FOR DAYS ...YEARS...I THINK SO....

EVERY TIME I START MY RIG IT HAS TO SUCK THE BOOSTER DOWN..
AND MESS'S UP THE CHOKE......

PLEASE ADVISE
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Old 04-03-2004, 11:50 PM   #2
Sweet72
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Wish I could be of help, but I too have had poor luck with boosters. Three used units so far, all worked for a while. Probably dry rotted diaphrams. I wonder if anyone sells the rebuild kits.
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Old 04-03-2004, 11:55 PM   #3
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WHAT SUCKS IS THESE ARE REMANUFACTURED UNITS
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Old 04-04-2004, 12:10 AM   #4
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Pedal is supposed to go down when you start truch after sitting awhile. To see if it is working (holding vacumn) start truck then cut off--pedal should have about 2 pedal pumps under boost and then just feel like it is solid. Mine works the way you describe yours.
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Old 04-04-2004, 02:11 AM   #5
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I lost my power brakes on a cross country trip in the '72. I was on I-40 headed east from Las Vegas to Maryland. Lost the boost in eastern New Mexico and tried to find a booster in several towns in Texas, and was told they could have it in a day or two. Well, I was in a hurry and low on cash so I fought that thing all the way to Nashville, where my brother met me with a used booster. Power brakes without vacuum is 4X worse than manual drum brakes!
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