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Re: Can booster hold vacuum and not boost [message #324740 is a reply to message #324732] Mon, 09 October 2017 10:42 Go to previous messageGo to previous message
wally is currently offline  wally   United States
Messages: 643
Registered: August 2004
Location: Omaha Nebraska
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Tilerpep wrote on Mon, 09 October 2017 08:01
Big update! The 78 Royale I got in January went around the block for the first time since April! Gas thanks in...now tuning and drivability.

I replaced almost everything on the bakes from the mc to the rear wheels. Mc, new lines, new rubber lines front and rear, new shoes pads, calipers. But it still took two feet on the pedal a few times. The vacuum booster looks original, holds a vacuum over time (it hisses when i pull of the one way valve) but the pedal feel indicates no real boost. I have an uninstalled metric booster from the P.O., but don't want to trade for the slow leak and figment problem to the mc that Dave lenzi has said can happen if this one is not the problem.

Also, i did not change the valve thing by driver wheel. Seems to me that if fluid flowed to bleed brakes, that valve isn't constricting. Include the info in case i may be wrong

On vehicle booster testing is described on page 5-37 of a service manual. I can send you a page scan, Pm with your email. Can't get the darn thing to copy paste on here.


Wally Anderson
Omaha NE
75 Glenbrook
 
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