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[GMCnet] Noisy Onan [message #333203] Thu, 07 June 2018 18:31 Go to next message
glwgmc is currently offline  glwgmc   United States
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Registered: June 2004
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Senior Member
The choke on the Onan is only pulled on while the starter is turning over. Once the starter stops turning the choke is not held closed electrically. I found that out while designing the kit that allows the Onan to run off either gasoline or propane at the flip of one DPDT toggle switch. I used that same choke circuit to open the propane bypass valve to allow propane to flow around the demand regulator while the starter was engaged. The other side of the DPDT toggle switch either powered the fuel pump (while on gasoline) or the propane shut off valve (while on propane). It is very easy to flood the Onan running on gasoline if the spark control is still via the old points. In that case the weak spark makes it hard to start keeping the starter motor engaged for longer than it was designed to be resulting in too much gas and wet plugs that do not fire well. Change out the spark control to a pertronics kit like the one developed by Gary Bovee and most Onan running/starting issues will be a thing of the past, especially if you run it off propane. It just is not worth the hassle to try to make that old thing run off gasoline unless you replace every rubber part that touched the ethanol laced junk now sold as gasoline. That includes the gaskets and o rings in the original fuel pump and carb, the line coming to the fuel pump, and including the tiny o ring in the carb. Then make sure you have cleaned the strainer in the carb and fiddle for way too long trying to get it adjusted to where it will run properly at idle and under load. With propane it is set, forget and enjoy unless something physically breaks inside the barbarian.

Jerry
Jerry Work
The Dovetail Joint
Fine furniture designed and hand crafted in the 1907 former Masonic Temple building in historic Kerby, OR

glwork@mac.com
http://jerrywork.com
============
Message: 5
Date: Thu, 7 Jun 2018 10:41:16 -0700
From: James Hupy
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Noisy Onan
Message-ID:

Content-Type: text/plain; charset="UTF-8"

The choke is kinda touchy when starting from cold. Usually, if you have a
problem on cold start, and you adjust for that, then when the unit is
warmed up, the choke is too rich. Touchy adjustment. Sometimes the ground
wire on the choke is rusty and corroded. A cleanup helps. Worth a try.
Jim Hupy

On Thu, Jun 7, 2018, 10:34 AM Deb McWade wrote:

> Got the Onan running, but not well I think. Sat for 4 days after getting
> it back, took about 15 seconds to start (sounded like wasn't getting fuel;
> fine on re-start). Since I have never had it running, and haven't heard
> another, I can't be certain, but I don't think it should sound like
> this....https://www.screencast.com/t/3dRknmXzB
>
> Oil, filter, etc all good, new fuel filter.
>
> Of course louder than is coming up here, like a metal fan striking the
> housing, but more intense. Any ideas about what I'm looking at here before
> I
> take the next step? Or you tell me what that should be ;)
>
> Thanks for your insight... I have none naturally. Deb
> --
> Deb McWade
> Logan Lake, BC, CAN
> "Li'l Sister"
> '77 Kingsley, 403, EBL EFI;
> TZE167V101404
> It's Bigger on the Inside!
>
>
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Jerry & Sharon Work
78 Royale
Kerby, OR
Re: [GMCnet] Noisy Onan [message #333208 is a reply to message #333203] Thu, 07 June 2018 19:20 Go to previous messageGo to next message
Deb is currently offline  Deb   Canada
Messages: 349
Registered: October 2016
Location: Logan Lake, BC
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Thanks Jerry - I do have the Bovee ignition system. Thought I would try to get it running before I went to the trouble of installing it in case she was totally beyond repair. But that is on my list of things to try to do in the next 5 days before I head out.

And I am very interested in converting it to propane! Get through this season (or at least this one trip) and then I'll be in touch for some information! Cheers. Deb


Deb McWade Logan Lake, BC, CAN GMC Alumnus It's Bigger on the Inside!
Re: [GMCnet] Noisy Onan [message #333215 is a reply to message #333208] Thu, 07 June 2018 20:29 Go to previous messageGo to next message
bdub is currently offline  bdub   United States
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Registered: February 2004
Location: Central Texas
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http://gmcws.org/blog/onan-on-propane-by-george-beckman/


On Thu, Jun 7, 2018 at 7:20 PM, Deb McWade wrote:

> Thanks Jerry - I do have the Bovee ignition system. Thought I would try
> to get it running before I went to the trouble of installing it in case she
> was totally beyond repair. But that is on my list of things to try to do
> in the next 5 days before I head out.
>
> And I am very interested in converting it to propane! Get through this
> season (or at least this one trip) and then I'll be in touch for some
> information! Cheers. Deb
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bdub
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Re: [GMCnet] Noisy Onan [message #333217 is a reply to message #333215] Thu, 07 June 2018 21:47 Go to previous message
Deb is currently offline  Deb   Canada
Messages: 349
Registered: October 2016
Location: Logan Lake, BC
Karma: 2
Senior Member
Thumbs Up bdub wrote on Thu, 07 June 2018 18:29
http://gmcws.org/blog/onan-on-propane-by-george-beckman/


On Thu, Jun 7, 2018 at 7:20 PM, Deb McWade wrote:

> Thanks Jerry - I do have the Bovee ignition system. Thought I would try
> to get it running before I went to the trouble of installing it in case she
> was totally beyond repair. But that is on my list of things to try to do
> in the next 5 days before I head out.
>
> And I am very interested in converting it to propane! Get through this
> season (or at least this one trip) and then I'll be in touch for some
> information! Cheers. Deb
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Deb McWade Logan Lake, BC, CAN GMC Alumnus It's Bigger on the Inside!
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