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auxiliary vacuum pump for brakes [message #370192] Mon, 25 July 2022 11:12 Go to next message
boybach is currently offline  boybach   
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Registered: December 2020
Location: Vancouver Island
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Senior Member
Due to my scary loss of braking power on Saturday due to engine stall, I've going to install a back up vacuum system. I checked out amazon and found these units.
brake vacuum pumps

They all look pretty similar but vary widely in price. They are marketed under different names but probably all from the same factory in China. I have no problem with that; most stuff is made there! In order to use one of these (any recommendations btw? I usually go with cheapest lol) I'm guessing I'll need a relay to switch it plus a pressure cut-off switch, a non-return valve and some plumbing, right?

any tips gratefully received as usual.

Thanks

Larry

Larry - Victoria BC - 1977 ex-Palm Beach "Ol' Leaky" 40,000 miles, PO said everything working but forgot the word NOT. Atwood helium fridge, water heater & furnace. SS exhaust system, Onan, Iota Converter, R134A, New fuel lines & heat exchange hoses

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Re: auxiliary vacuum pump for brakes [message #370194 is a reply to message #370192] Mon, 25 July 2022 17:07 Go to previous messageGo to next message
dmumert is currently offline  dmumert   Canada
Messages: 46
Registered: December 2006
Location: Canada
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Member
Check out this one. It shows the vacuum switch and valve options.

https://www.amazon.ca/ACDelco-178-0884-Original-Equipment-Assembly/dp/B00B4KS92Q

You may need to find appropriate connectors

Dave

Dave Mumert Olds, AB

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Re: auxiliary vacuum pump for brakes [message #370195 is a reply to message #370192] Mon, 25 July 2022 17:47 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Registered: March 2007
Location: S.E. Michigan
Karma: 7
Senior Member
Larry,
Most of those are the same pump so don't get suckered in. Buy one and a transmission vacuum switch.
https://www.amazon.ca/Superior-K058-Universal-Adjustable-Vacuum/dp/B0778KLW7H/ref=sr_1_2?crid=3URBTDLUIGG2K&keywords=transmission+vacuum+switch&am p;qid=1658789018&s=automotive&sprefix=transmission+vaccum+switch%2Cautomotive%2C193&sr=1-2
To turn it on.
Plumbing into the booster is also interesting, but well worth doing.
With that pump set up for 16"hg, if you pop the booster you will have brakes again in about 5 seconds. (That can be a very long 5 seconds.)
What is comforting is to hear the pump run before you start a cold engine.
Matt

Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit

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Re: auxiliary vacuum pump for brakes [message #370198 is a reply to message #370195] Mon, 25 July 2022 20:38 Go to previous messageGo to next message
Bill Van Vlack is currently offline  Bill Van Vlack   United States
Messages: 419
Registered: September 2015
Location: Guemes Island, Washington
Karma: 14
Senior Member
Jeep supply houses have brackets for them for moving the jeep pump from the bumper area to the hood opening to make way for a winch. Easy way to mount them.

https://www.amazon.com/EAG-Steel-Vacuum-Relocation-Bracket/dp/B075H6HVD5

Bill Van Vlack '76 Royale; Guemes Island, Washington; Twin bed, full (DS) side bath, Brazilian Redwood counter and settee tops,455, 6KW generator; new owner a/o mid November 2015.

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Re: auxiliary vacuum pump for brakes [message #370225 is a reply to message #370192] Thu, 28 July 2022 15:10 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
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Hi Dave

Long time no hear.

I had plans of coming your way and on to northern BC in July. It never happened again. So another summer passes and I never got to Alberta. This time it was medical with very sore back and ribs. So I do not drive over about 30 miles. If it gets it gets cleared up summer will probably be over.

I am happy to see you around again.

Ken Burton

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

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Re: auxiliary vacuum pump for brakes [message #370258 is a reply to message #370192] Wed, 03 August 2022 13:55 Go to previous message
Tilerpep is currently offline  Tilerpep   United States
Messages: 404
Registered: June 2013
Location: Raleigh, NC
Karma: 7
Senior Member
The passive brake booster reservoir has pros and cons, but I have them on both my coaches. I just posted in another thread that mine yields four full regular stops, and two more "better than nothing".

http://www.gmcmhphotos.com/photos/miscellaneous-gmc-stuff/p3868.html
pic to get you started

1975 Glenbrook, 1978 Royale rear bath Raleigh, NC

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