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[GMCnet] vacuum pump installation for idiots [message #124824] Fri, 06 May 2011 11:16 Go to next message
KB is currently offline  KB   United States
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Registered: September 2009
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I've been going through the available info for installing a jc4
vacuum pump for the brakes, but still don't have it quite figured out.

The brake booster we've got has two taps (inlets?) instead of just one.
Should I just plumb the jc4 to the extra tap and leave the
other side of the pump open? All the instructions are for a single
inlet booster.

I see how we can use the yellow wire for the accessory input, but
where should I get the 12-volt power? Is this a 10-gauge wire run directly
to the battery, or can/should it be from somewhere else?

The horror stories make me really want one of these!

thanks,
Karen
1973 23'
1975 26'
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Karen 1975 26' San Jose, CA

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Re: [GMCnet] vacuum pump installation for idiots [message #124826 is a reply to message #124824] Fri, 06 May 2011 11:34 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Karen,

Connect one of the check valves on the front of the booster to the engine
manifold and the second one to the aux vacuum pump.

You probably have found this but just in case:

http://www.gmcmhphotos.com/photos/showphoto.php?photo=23813

Regards,
Rob M.
USAussie - Downunder
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426

-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of KB
Sent: Friday, May 06, 2011 12:16 PM
To: gmclist@temp.gmcnet.org
Subject: [GMCnet] vacuum pump installation for idiots

I've been going through the available info for installing a jc4
vacuum pump for the brakes, but still don't have it quite figured out.

The brake booster we've got has two taps (inlets?) instead of just one.
Should I just plumb the jc4 to the extra tap and leave the
other side of the pump open? All the instructions are for a single
inlet booster.

I see how we can use the yellow wire for the accessory input, but
where should I get the 12-volt power? Is this a 10-gauge wire run directly
to the battery, or can/should it be from somewhere else?

The horror stories make me really want one of these!

thanks,
Karen
1973 23'
1975 26'
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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426

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Re: [GMCnet] vacuum pump installation for idiots [message #124837 is a reply to message #124824] Fri, 06 May 2011 12:27 Go to previous messageGo to next message
n6mon is currently offline  n6mon   United States
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Registered: January 2004
Location: San Lorenzo, CA
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On 5/6/2011 10:35 AM, mr.erfisher@gmail.com wrote:
> Ask 3 gmc-ers ,get 5 answers :)
and at least 1 of them will be right :-)
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Terry Taylor
'74 ex-Eleganza SE
San Lorenzo, CA
http://www.n6mon.org
http://dldesignstore.com

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Re: [GMCnet] vacuum pump installation for idiots [message #124838 is a reply to message #124826] Fri, 06 May 2011 12:30 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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Registered: August 2005
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Senior Member
Put the pump between the engine and the booster--- existing connections---it was designed for this configuration.

Ask 3 gmc-ers ,get 5 answers :)

Gene

FREE WIFI




On May 6, 2011, at 9:34 AM, "Rob Mueller" <robmueller@iinet.net.au> wrote:

> Karen,
>
> Connect one of the check valves on the front of the booster to the engine
> manifold and the second one to the aux vacuum pump.
>
> You probably have found this but just in case:
>
> http://www.gmcmhphotos.com/photos/showphoto.php?photo=23813
>
> Regards,
> Rob M.
> USAussie - Downunder
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
>
> -----Original Message-----
> From: gmclist-bounces@temp.gmcnet.org
> [mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of KB
> Sent: Friday, May 06, 2011 12:16 PM
> To: gmclist@temp.gmcnet.org
> Subject: [GMCnet] vacuum pump installation for idiots
>
> I've been going through the available info for installing a jc4
> vacuum pump for the brakes, but still don't have it quite figured out.
>
> The brake booster we've got has two taps (inlets?) instead of just one.
> Should I just plumb the jc4 to the extra tap and leave the
> other side of the pump open? All the instructions are for a single
> inlet booster.
>
> I see how we can use the yellow wire for the accessory input, but
> where should I get the 12-volt power? Is this a 10-gauge wire run directly
> to the battery, or can/should it be from somewhere else?
>
> The horror stories make me really want one of these!
>
> thanks,
> Karen
> 1973 23'
> 1975 26'
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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Re: [GMCnet] vacuum pump installation for idiots [message #124845 is a reply to message #124837] Fri, 06 May 2011 13:01 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
Karma: 13
Senior Member

On May 6, 2011, at 11:27 AM, Terry Taylor wrote:

>
>
> On 5/6/2011 10:35 AM, mr.erfisher@gmail.com wrote:
>> Ask 3 gmcers ,get 5 answers :)
> and at least 1 of them will be right :-)

Not necessarily! :)

Emery Stora
77 Kingsley
Santa Fe, NM


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Re: [GMCnet] vacuum pump installation for idiots [message #124847 is a reply to message #124838] Fri, 06 May 2011 13:34 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Gene,

I'm confused!

If the engine dies won't the vacuum pump try to pull a vacuum through the
hose and intake manifold?

Regards,
Rob M.
USAussie - Downunder
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426

-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of mr.erfisher@gmail.com
Sent: Friday, May 06, 2011 1:36 PM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] vacuum pump installation for idiots

Put the pump between the engine and the booster--- existing connections---it
was designed for this configuration.

Ask 3 gmc-ers ,get 5 answers :)

Gene

FREE WIFI




On May 6, 2011, at 9:34 AM, "Rob Mueller" <robmueller@iinet.net.au> wrote:

> Karen,
>
> Connect one of the check valves on the front of the booster to the engine
> manifold and the second one to the aux vacuum pump.
>
> You probably have found this but just in case:
>
> http://www.gmcmhphotos.com/photos/showphoto.php?photo=23813
>
> Regards,
> Rob M.
> USAussie - Downunder
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
>
> -----Original Message-----
> From: gmclist-bounces@temp.gmcnet.org
> [mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of KB
> Sent: Friday, May 06, 2011 12:16 PM
> To: gmclist@temp.gmcnet.org
> Subject: [GMCnet] vacuum pump installation for idiots
>
> I've been going through the available info for installing a jc4
> vacuum pump for the brakes, but still don't have it quite figured out.
>
> The brake booster we've got has two taps (inlets?) instead of just one.
> Should I just plumb the jc4 to the extra tap and leave the
> other side of the pump open? All the instructions are for a single
> inlet booster.
>
> I see how we can use the yellow wire for the accessory input, but
> where should I get the 12-volt power? Is this a 10-gauge wire run
directly
> to the battery, or can/should it be from somewhere else?
>
> The horror stories make me really want one of these!
>
> thanks,
> Karen
> 1973 23'
> 1975 26'
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426

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Re: [GMCnet] vacuum pump installation for idiots [message #124850 is a reply to message #124847] Fri, 06 May 2011 13:56 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
Karma: 13
Senior Member

On May 6, 2011, at 12:34 PM, Rob Mueller wrote:

> Gene,
>
> I'm confused!
>
> If the engine dies won't the vacuum pump try to pull a vacuum through the
> hose and intake manifold?
>
> Regards,
> Rob M.

Not Gene, but that is how I have had mine for several years.
It pulls a vacuum from the booster and exhausts into the intake manifold (or put otherwise it is in series with the booster and intake manifold).

If there is enough vacuum drawn by the intake manifold then the pump never comes on. if there is not enough vacuum drawn by the intake manifold then the pump provides the vacuum for the booster.

Emery Stora
77 Kingsley
Santa Fe, NM


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Re: [GMCnet] vacuum pump installation for idiots [message #124852 is a reply to message #124850] Fri, 06 May 2011 14:07 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
Messages: 7111
Registered: November 2004
Location: Dexter, Mo.
Karma: 207
Senior Member
Depending on coach year where you get voltage. 73-4, don't wire it to heater. 75 up you can do that.
Dan

3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer

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Re: [GMCnet] vacuum pump installation for idiots [message #124857 is a reply to message #124847] Fri, 06 May 2011 14:29 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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Registered: August 2005
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Senior Member
here is the way it is hooked up
http://goo.gl/t4zIV

the pump is built to go between the manifold (engine vac) -- pump--
booster.

that way when the engine is running and has vac, the pump is designed not to
run.

when the engine is stopped (no vac) the pump senses no vac and will turn on,
sucking on the booster till no more vac is needed, then the pump will stop.
The pump will continue to suck the booser until the power is off, or the
engine starts (vac supply)

the pump is in series between the engine and the booster.

no additional check valves required.

this is the way our original 119 pumps were plumbed .
http://goo.gl/A4SMa

gene

'
gene


> If the engine dies won't the vacuum pump try to pull a vacuum through the
> hose and intake manifold?
>

--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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Re: [GMCnet] vacuum pump installation for idiots [message #124893 is a reply to message #124845] Fri, 06 May 2011 19:15 Go to previous messageGo to next message
mike miller   United States
Messages: 3576
Registered: February 2004
Location: Hillsboro, Oregon
Karma: 0
Senior Member
emerystora wrote on Fri, 06 May 2011 11:01


>> Ask 3 gmcers ,get 5 answers Smile
> and at least 1 of them will be right Smile

Not necessarily! Smile


The reader needs to evaluate the "answers." One MIGHT be right for his (or her) situation.

GMCnet, money back if not satisfied... Oh that's right... you didn't pay anything for the advice! Twisted Evil

Mike Miller -- Hillsboro, OR -- on the Black list
(#2)`78 23' Birchaven Rear Bath -- (#3)`77 23' Birchaven Side Bath
More Sidekicks than GMC's and a late model Malibu called 'Boo' http://m000035.blogspot.com

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Re: [GMCnet] vacuum pump installation for idiots [message #124900 is a reply to message #124850] Fri, 06 May 2011 19:43 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Emery,

Got it! THANKS!

It's in series with the engine manifold.

I pictured the aux pump inlet "T'd" into the line that ran from the engine
to the booster and the pump outlet dumping to ambient.

My aux pump connects to the second check valve on the booster and the outlet
dumps to ambient.

Regards,
Rob M.
USAussie - Downunder
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426


-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Emery Stora
Sent: Friday, May 06, 2011 2:56 PM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] vacuum pump installation for idiots

Not Gene, but that is how I have had mine for several years.
It pulls a vacuum from the booster and exhausts into the intake manifold (or
put otherwise it is in series with the booster and intake manifold).

If there is enough vacuum drawn by the intake manifold then the pump never
comes on. if there is not enough vacuum drawn by the intake manifold then
the pump provides the vacuum for the booster.

Emery Stora
77 Kingsley
Santa Fe, NM


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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426

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Re: [GMCnet] vacuum pump installation for idiots [message #124903 is a reply to message #124824] Fri, 06 May 2011 19:57 Go to previous messageGo to next message
KB is currently offline  KB   United States
Messages: 1262
Registered: September 2009
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Senior Member

> My aux pump connects to the second check valve on the booster and the outlet
> dumps to ambient.

Thanks, I'll try it that way since I've got two check valves on the booster.
Did you put a filter in there? Or is that not needed since it's not
hooked to the manifold?


thanks,
Karen
1973 23'
1975 26'

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Re: [GMCnet] vacuum pump installation for idiots [message #124916 is a reply to message #124903] Fri, 06 May 2011 21:06 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Location: Sydney, Australia
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Karen,

No filter but Ken H. did put a screen over the pump outlet to keep mud
daubers out!

Regards,
Rob M.
USAussie - Downunder
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426

-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of KB
Sent: Friday, May 06, 2011 8:57 PM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] vacuum pump installation for idiots

Thanks, I'll try it that way since I've got two check valves on the booster.
Did you put a filter in there? Or is that not needed since it's not
hooked to the manifold?


thanks,
Karen
1973 23'
1975 26'

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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426

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Re: [GMCnet] vacuum pump installation for idiots [message #124968 is a reply to message #124824] Sat, 07 May 2011 11:17 Go to previous message
KB is currently offline  KB   United States
Messages: 1262
Registered: September 2009
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Ahhh, critters! When I took apart the '73 coach interior, I found
a big cache of acorns at the back of the propane compartment.
But I think Marsha's possum babies are the best. :-)

>
> No filter but Ken H. did put a screen over the pump outlet to keep mud
> daubers out!

thanks,
Karen
1973 23'
1975 26'

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Karen 1975 26' San Jose, CA

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