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Onan carb float [message #243775] Sun, 16 March 2014 14:18 Go to next message
gbarrow2 is currently offline  gbarrow2   United States
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What's the trick to getting the float bowl re-installed without binding the float?

With the bowl off and the needle and float in place I can blow through the inlet tube and the float and needle move freely.

When I screw the bowl in place the needle seals in the seat and I cant blow through inlet.

I've had this apart in the past and it went back together with no problem.

Few days ago Onan was running for a while and died. Got spark, fuel in the tank, and the pump is working. Wouldn't re-start.

After trying to start today with no success- removed float bowl and it was bone dry. No fuel getting past the inlet valve.

Suggestions please.


Gene Barrow
Lake Almanor, Ca.
1976 Palm Beach
Re: [GMCnet] Onan carb float [message #243777 is a reply to message #243775] Sun, 16 March 2014 14:30 Go to previous messageGo to next message
Kingsley Coach is currently offline  Kingsley Coach   United States
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Location: Nova Scotia Canada
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Senior Member
Re Onan
There is an electrical in line shut off just in front of where the fuel
line enters the filter. It has 2 (I think) wires attached to it. Remove
that as it is not required and perhaps the gas will flow easier to the pump.
You asked for suggestions...<g>

Mike in NS


On Sun, Mar 16, 2014 at 4:18 PM, gene barrow <barrowgene@gmail.com> wrote:

>
>
> What's the trick to getting the float bowl re-installed without binding
> the float?
>
> With the bowl off and the needle and float in place I can blow through the
> inlet tube and the float and needle move freely.
>
> When I screw the bowl in place the needle seals in the seat and I cant
> blow through inlet.
>
> I've had this apart in the past and it went back together with no problem.
>
> Few days ago Onan was running for a while and died. Got spark, fuel in the
> tank, and the pump is working. Wouldn't re-start.
>
> After trying to start today with no success- removed float bowl and it
> was bone dry. No fuel getting past the inlet valve.
>
> Suggestions please.
>
> --
> Gene Barrow
> Lake Almanor, Ca.
> 1976 Palm Beach
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Michael Beaton
1977 Kingsley 26-11
1977 Eleganza II 26-3
Antigonish, NS

* At my age, getting lucky means walking into a room and remembering what I
came for.
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Re: Onan carb float [message #243778 is a reply to message #243775] Sun, 16 March 2014 14:36 Go to previous messageGo to next message
Otterwan   United States
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Sounds like you have something installed wrong. The bowl shouldn't interfere with the float at all. I'd take the bowl off and give everything a once over to make sure you didn't miss something.

1977 Birchaven, Lynnwood WA - "We may not be able to stop all evil in the world, but I know that how we treat one another is entirely up to us."
Re: [GMCnet] Onan carb float [message #243781 is a reply to message #243778] Sun, 16 March 2014 14:45 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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GENE, on some of the walbro carbs on Onan engines, there is a flat area on
the bottom of the bowl. That should be aligned with the low side of the
float, or it will hold the inlet valve closed when bowl is installed. Also
on some applications, there is a fiber washer on both the inside as well as
the outside of the bolt in the center of the bowl, or adjustable jet
needle, depending upon application.
JIM Hupy
Salem, Oregon
78 GMC Royale 403
On Mar 16, 2014 12:36 PM, "David Orders" <dao@oarsllc.com> wrote:

>
>
> Sounds like you have something installed wrong. The bowl shouldn't
> interfere with the float at all. I'd take the bowl off and give everything
> a once over to make sure you didn't miss something.
> --
> 1976 Royale "Twinkie II", 1978 Palm Beach with front end fire. Lynnwood WA
> - "We may not be able to stop all evil in the world, but I know that how we
> treat one another is entirely up to us."
> _______________________________________________
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Re: [GMCnet] Onan carb float [message #243783 is a reply to message #243777] Sun, 16 March 2014 14:54 Go to previous messageGo to next message
gbarrow2 is currently offline  gbarrow2   United States
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Mike,
Thanks for suggestion, but I've got plenty of fuel down stream past that point. Not the issue.

Carb is off the engine.

At this point I'm just trying to get AIR to pass the needle and seat with float bowl installed. If air wont pass neither will fuel.


Gene Barrow
Lake Almanor, Ca.
1976 Palm Beach
Re: Onan carb float [message #243787 is a reply to message #243778] Sun, 16 March 2014 15:19 Go to previous messageGo to next message
gbarrow2 is currently offline  gbarrow2   United States
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David,
Only 4 parts involved-only goes together one way and I have checked it numerous times. Not saying I'm not missing something- just can't see what it is.

Jim,
My float bowl is flat all the way around the bottom- no raised portion. It has 2 fiber washers. One inside and one outside the bowl.


Gene Barrow
Lake Almanor, Ca.
1976 Palm Beach
Re: [GMCnet] Onan carb float [message #243790 is a reply to message #243787] Sun, 16 March 2014 15:43 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Then, it is probably the inlet seat. They are made today of a material
called "viton" or similar, and are alcohol resistant. The original ones
were not resistant, and they get soft and gummy when they are exposed to
alcohol fuels. They can be changed out, I usually just turn an appropriate
sized screw into them and pry them out. The new one is easily damaged
during install. I usually use a piece of drill rod that just fits the seat
bore, and press it in by hand. Darn gummy fuels anyhow. We just have to
keep coming up with band aid fixes for these dinosaurs, in spite of what
kinds of fuel blends we are faced with.
Jim Hupy
Salem, OR
78 GMC Royale 403


On Sun, Mar 16, 2014 at 1:19 PM, gene barrow <barrowgene@gmail.com> wrote:

>
>
> David,
> Only 4 parts involved-only goes together one way and I have checked it
> numerous times. Not saying I'm not missing something- just can't see what
> it is.
>
> Jim,
> My float bowl is flat all the way around the bottom- no raised portion. It
> has 2 fiber washers. One inside and one outside the bowl.
> --
> Gene Barrow
> Lake Almanor, Ca.
> 1976 Palm Beach
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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Re: [GMCnet] Onan carb float [message #243813 is a reply to message #243790] Sun, 16 March 2014 17:25 Go to previous messageGo to next message
gbarrow2 is currently offline  gbarrow2   United States
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Jim,
The seat does feel mushy/springy when I push on the needle.

Where would I obtain a replacement seat, needle, or complete valve. Can it be matched from more common carb kits?

Thanks


Gene Barrow
Lake Almanor, Ca.
1976 Palm Beach
Re: [GMCnet] Onan carb float [message #243814 is a reply to message #243813] Sun, 16 March 2014 17:38 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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gbarrow wrote on Sun, 16 March 2014 17:25

Jim,
The seat does feel mushy/springy when I push on the needle.

Where would I obtain a replacement seat, needle, or complete valve. Can it be matched from more common carb kits?

Thanks
http://www.appliedgmc.com/prod.itml/icOid/892
Re: [GMCnet] Onan carb float [message #243816 is a reply to message #243813] Sun, 16 March 2014 17:41 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Registered: May 2010
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WALBRO carbs are fairly common. I would try an outdoor power shop. Take the
carb with you and plead upon their good nature. Last resort/ Cummins/Onan.
ALSO Jim K. is now an approved ONAN dealer. Call Nick and ask him.
JIM Hupy
On Mar 16, 2014 3:25 PM, "gene barrow" <barrowgene@gmail.com> wrote:

>
>
> Jim,
> The seat does feel mushy/springy when I push on the needle.
>
> Where would I obtain a replacement seat, needle, or complete valve. Can it
> be matched from more common carb kits?
>
> Thanks
> --
> Gene Barrow
> Lake Almanor, Ca.
> 1976 Palm Beach
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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Re: [GMCnet] Onan carb float [message #243850 is a reply to message #243816] Sun, 16 March 2014 20:00 Go to previous messageGo to next message
gbarrow2 is currently offline  gbarrow2   United States
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Well, as luck (bad or good?) would have it I will be in Jim K's area on Tuesday. So if I don't find any thing local tomorrow I'll go see Jim.

Thanks to all for suggestions.
I betting Jim H. has it right- inlet seat FUBAR due to too much alcohol. If it does this to hard rubber parts I'm afraid to find out what it's doing to my liver!


Gene Barrow
Lake Almanor, Ca.
1976 Palm Beach
Re: Onan carb float [message #243851 is a reply to message #243775] Sun, 16 March 2014 20:03 Go to previous messageGo to next message
WildBill   Canada
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Now that's funny!
Re: Onan carb float [message #243865 is a reply to message #243775] Sun, 16 March 2014 21:26 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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They should take the ethyl alcohol out of gas and use it to boost the proof on Kentucky whiskey.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: Onan carb float [message #244181 is a reply to message #243775] Tue, 18 March 2014 18:56 Go to previous messageGo to next message
Bob de Kruyff   United States
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Location: Chandler, AZ
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gbarrow wrote on Sun, 16 March 2014 13:18

What's the trick to getting the float bowl re-installed without binding the float?

With the bowl off and the needle and float in place I can blow through the inlet tube and the float and needle move freely.

When I screw the bowl in place the needle seals in the seat and I cant blow through inlet.

I've had this apart in the past and it went back together with no problem.

Few days ago Onan was running for a while and died. Got spark, fuel in the tank, and the pump is working. Wouldn't re-start.

After trying to start today with no success- removed float bowl and it was bone dry. No fuel getting past the inlet valve.

Suggestions please.


When you blow into the fuel inlet with the bowl off--you blow into the atmosphere through the float needle. When the bowl is on, the only place for the air to go is through the main jet (I don't think the bowl is ventilated but could be wrong. I would unscrew the main jet which is the one at the bottom of the bowl and then try it again. The air has to go somwhere and something upstream is plugged or closed.


Bob de Kruyff
78 Eleganza
Chandler, AZ
Re: Onan carb float [message #244191 is a reply to message #243775] Tue, 18 March 2014 20:43 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
Messages: 4508
Registered: April 2011
Karma: 39
Senior Member
gbarrow wrote on Sun, 16 March 2014 14:18

What's the trick to getting the float bowl re-installed without binding the float?

With the bowl off and the needle and float in place I can blow through the inlet tube and the float and needle move freely.

When I screw the bowl in place the needle seals in the seat and I cant blow through inlet.

I've had this apart in the past and it went back together with no problem.

Few days ago Onan was running for a while and died. Got spark, fuel in the tank, and the pump is working. Wouldn't re-start.

After trying to start today with no success- removed float bowl and it was bone dry. No fuel getting past the inlet valve.

Suggestions please.
The procedure for setting the float is in the Maintenance Manual. Maintenance Manuals vary by year, so I don't know what section it would be in for your year model.
Re: [GMCnet] Onan carb float [message #244226 is a reply to message #243865] Wed, 19 March 2014 06:37 Go to previous message
jhbridges is currently offline  jhbridges   United States
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Location: Braselton ga
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Senior Member
The problem is, it then becomes 'Blended' instead of "Bourbon" and at that point it is best poured back into the horse.

--johnny
'76 23' transmode norris


________________________________
From: John R. Lebetski <gransport@aol.com>
To: gmclist@temp.gmcnet.org
Sent: Sunday, March 16, 2014 10:26 PM
Subject: Re: [GMCnet] Onan carb float




They should take the ethyl alcohol out of gas and use it to boost the proof on Kentucky whiskey.
--
John Lebetski
Chicago, IL
77 Eleganza II
Source America First

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Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
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