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Aux vacuum pump whistle [message #206397] Tue, 30 April 2013 08:53 Go to next message
biggreen is currently offline  biggreen   United States
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Registered: June 2011
Location: Northeast Florida
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Recently installed a JC4 Aux. vacuum pump. Works fine, but emits a loud whistle when operating and until it empties. I assume its leaking from the grommet on the booster.
Anyone have a part # for this grommet, or any other solution?
Thanks.

77Palm Beach 403
Re: [GMCnet] Aux vacuum pump whistle [message #206398 is a reply to message #206397] Tue, 30 April 2013 09:05 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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mount it in series with the manifold vacuum like this

http://www.gmcmhphotos.com/photos/vacuum-booster-pump-auxiliary-gmc-jc4/p27712-yeager.html

good luck
gene


On Tue, Apr 30, 2013 at 6:53 AM, R.D. Hart <regor5556@yahoo.com> wrote:

>
>
> Recently installed a JC4 Aux. vacuum pump. Works fine, but emits a loud
> whistle when operating and until it empties. I assume its leaking from the
> grommet on the booster.
> Anyone have a part # for this grommet, or any other solution?
> Thanks.
>
> 77Palm Beach 403
> _______________________________________________
> GMCnet mailing list
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--
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] Aux vacuum pump whistle [message #206405 is a reply to message #206398] Tue, 30 April 2013 10:03 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Registered: July 2007
Location: Sydney, Australia
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Senior Member
RD,

Seems to me that it would be a bit easier to drive the GMC to AutoZone and buy a new grommet:

http://tinyurl.com/c8f95ex

http://www.autozone.com/autozone/accessories/Help-1-2-in-i-d-grommet-fits-3-4-in-dia-hole-and-13-16-in-i-d-grommet-fits-1-1-16-in-di
a-hole-fits-most-common-brake-check-valves/_/N-25pd?itemIdentifier=237990_0_0_

Regards,
Rob M.

-----Original Message-----
From: gene Fisher

mount it in series with the manifold vacuum like this

http://www.gmcmhphotos.com/photos/vacuum-booster-pump-auxiliary-gmc-jc4/p27712-yeager.html

good luck
gene

On Tue, Apr 30, 2013 at 6:53 AM, R.D. Hart <regor5556@yahoo.com> wrote:

> Recently installed a JC4 Aux. vacuum pump. Works fine, but emits a loud
> whistle when operating and until it empties. I assume its leaking from the
> grommet on the booster.
> Anyone have a part # for this grommet, or any other solution?
> Thanks.
>
> 77Palm Beach 403

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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
Re: Aux vacuum pump whistle [message #206408 is a reply to message #206397] Tue, 30 April 2013 10:30 Go to previous messageGo to next message
mike miller   United States
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Registered: February 2004
Location: Hillsboro, Oregon
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Senior Member
biggreen wrote on Tue, 30 April 2013 06:53

Recently installed a JC4 Aux. vacuum pump. Works fine, but emits a loud whistle when operating and until it empties. I assume its leaking from the grommet on the booster.
Anyone have a part # for this grommet, or any other solution?
Thanks.

77Palm Beach 403


Rob has pointed you to a source fof a gromet. But....

Seems to me that for us to properly help you troubleshoot, we would need to know how your jc4 is installed. There are a couple of ways that work.



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
Re: Aux vacuum pump whistle [message #206409 is a reply to message #206408] Tue, 30 April 2013 11:03 Go to previous messageGo to next message
biggreen is currently offline  biggreen   United States
Messages: 347
Registered: June 2011
Location: Northeast Florida
Karma: 1
Senior Member

Good point. Mine is plugged directly into the booster, with a filter on the way back to the motor.

Mike Miller wrote on Tue, 30 April 2013 10:30

biggreen wrote on Tue, 30 April 2013 06:53

Recently installed a JC4 Aux. vacuum pump. Works fine, but emits a loud whistle when operating and until it empties. I assume its leaking from the grommet on the booster.
Anyone have a part # for this grommet, or any other solution?
Thanks.

77Palm Beach 403


Rob has pointed you to a source fof a gromet. But....

Seems to me that for us to properly help you troubleshoot, we would need to know how your jc4 is installed. There are a couple of ways that work.



Re: Aux vacuum pump whistle [message #206417 is a reply to message #206409] Tue, 30 April 2013 11:23 Go to previous message
mike miller   United States
Messages: 3576
Registered: February 2004
Location: Hillsboro, Oregon
Karma: 0
Senior Member
So if it "whistles" while the pump is running and continues after you shut the pump off. It does sound like a vacuum leak. (Does it also whistle with the pump off and the motor running?)

As long as the pump is plug directly into the booster and the pump is in-line with the vacuum line to the intake, the leak can only be the pump, the booster or the grommet. Double check that the grommet is still in position and then replace it. While you have the pump off, you should be able to check it. Plug the booster side and turn it on. It should pump for a very short time and stop as it pulls a vacuum on your plug.

I assume the booster was fine before you added the JC4.

biggreen wrote on Tue, 30 April 2013 09:03


Good point. Mine is plugged directly into the booster, with a filter on the way back to the motor.



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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