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Onan Fuel Pump Assembly [message #166424] Sun, 15 April 2012 14:50 Go to next message
jcurran is currently offline  jcurran   United States
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My fuel pump stopped sucking. I dis-assembled it and was pretty clean inside. But I was wondering: there are two plastic check valves. Are they BOTH supposed to be spring-loaded ? The upper check valve is not, in my case.

When I apply AC power, the pump vibrates but it can't seem to move any fluid. The upper check valve rarely seats properly when I fiddle with it so I was wondering about a missing spring.

Thanks,
Jim

Jim Curran 1976 Palm Beach Alexandria, OH

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Re: [GMCnet] Onan Fuel Pump Assembly [message #166430 is a reply to message #166424] Sun, 15 April 2012 15:41 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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did you look through these ?

http://www.gmcmhphotos.com/photos/showphoto.php?photo=7105&cat=3636

gene



On Sun, Apr 15, 2012 at 12:50 PM, Jim Curran <jim.curran@tfcci.com> wrote:

>
>
> My fuel pump stopped sucking. I dis-assembled it and was pretty clean
> inside. But I was wondering: there are two plastic check valves. Are they
> BOTH supposed to be spring-loaded ? The upper check valve is not, in my
> case.
>
> When I apply AC power, the pump vibrates but it can't seem to move any
> fluid. The upper check valve rarely seats properly when I fiddle with it
> so I was wondering about a missing spring.
>
> Thanks,
> Jim
> --
> Jim Curran
> 1976 Palm Beach
> Alexandria, OH
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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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
-------
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Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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Re: Onan Fuel Pump Assembly [message #166431 is a reply to message #166424] Sun, 15 April 2012 15:59 Go to previous messageGo to next message
kingd is currently offline  kingd   Canada
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Jim Curran, I hope your are not really applying AC power as you stated in your post !!!!

DAVE KING

DAVE KING lurker, wannabe Toronto, Ontario, Canada

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Re: Onan Fuel Pump Assembly [message #166434 is a reply to message #166424] Sun, 15 April 2012 16:50 Go to previous messageGo to next message
Galen is currently offline  Galen   United States
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For what it's worth, when I first tried to get my Onan running after the previous owner had it setting for years, I thought the fuel pump was bad. It turned out that the fuel line to the pump either had a pin hole or was leaking/sucking air at a fitting because when I replaced that, it worked just fine.

Galen

Galen Briggs New Virginia, Iowa 1978 Palm Beach

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Re: Onan Fuel Pump Assembly [message #166435 is a reply to message #166431] Sun, 15 April 2012 16:54 Go to previous messageGo to next message
jcurran is currently offline  jcurran   United States
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The plastic valve I am referring to is in this photo:

http://www.gmcmhphotos.com/photos/showphoto.php?photo=7113&cat=3636

When I applied 24VAC, , the pump hummed. In a fit of frustration, I smacked it and it started rattling and pumped air nicely. Put it back on the coach. Working.

In any case, the generator is out there humming along as I type this but I'd still like to know about the check valve if anyone knows.


Jim

Jim Curran 1976 Palm Beach Alexandria, OH

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Re: Onan Fuel Pump Assembly [message #166440 is a reply to message #166435] Sun, 15 April 2012 17:52 Go to previous messageGo to next message
Dennis S is currently offline  Dennis S   United States
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Jim,

Doesn't this photo show you the parts breakdown?

http://www.gmcmhphotos.com/photos/showphoto.php?photo=7112&cat=3636

No spring load except on the lower end from my memory of disassembly.

Dennis

jcurran wrote on Sun, 15 April 2012 16:54

The plastic valve I am referring to is in this photo:

http://www.gmcmhphotos.com/photos/showphoto.php?photo=7113&cat=3636

When I applied 24VAC, , the pump hummed. In a fit of frustration, I smacked it and it started rattling and pumped air nicely. Put it back on the coach. Working.

In any case, the generator is out there humming along as I type this but I'd still like to know about the check valve if anyone knows.


Jim

Dennis S
73 Painted Desert 230
Memphis TN Metro

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Re: Onan Fuel Pump Assembly [message #166445 is a reply to message #166440] Sun, 15 April 2012 18:22 Go to previous message
jcurran is currently offline  jcurran   United States
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Registered: May 2009
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Dennis,

That dis-assembly photo was very helpful and I used it while re-assembling. But on a subsequent dis-assembly I realized the valve in the moving cylinder wasn't spring-loaded.

The fact that the generator is running might suggest that it doesn't matter. I was also concerned there might be broken spring metal downstream of the pump.

Jim

Jim Curran 1976 Palm Beach Alexandria, OH

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