GMCforum: GMCnet » [GMCnet] Onan Problem

Home » Public Forums » GMCnet » [GMCnet] Onan Problem

Show: Today's Messages :: Polls :: Message Navigator

[GMCnet] Onan Problem [message #70222]

Sat, 09 January 2010 14:46

George Zhookoff

Messages: 398
Registered: December 2004
Location: Snellville, GA

Karma: 6

Senior Member

When I try to start Onan I push prime button and unit starts. But when I release prime button Onan stops. This is the prime circuit add on in the start panel.
Any ideas?
We're day trip to Motorcycle show in Greenville, SC.
Tia,
George Zhookoff
78 EL II
Atlanta
_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

Report message to a moderator

Re: [GMCnet] Onan Problem [message #70227 is a reply to message #70222]

Sat, 09 January 2010 15:18

GMCWiperMan

Messages: 1248
Registered: December 2007

Karma: 1

Senior Member

George,

When you push the prime button, you simply take +12 VDC from a panel source
and send it "backward" through the Run Time Meter wire to the ignition
coil's primary. So obviously the control board is not supplying +12 VDC to
the coil (and fuel pump) after the engine starts. The first thing to check
is the fuse on the circuit board. Then go through the troubleshooting
procedure in Duane Simmons' Onan booklet from
http://www.gmcws.org/Tech/dsimmons/dsimmons.html

Ken H.
Americus, GA
'76 X-Birchaven
www.gmcwipersetc.com

On Sat, Jan 9, 2010 at 3:46 PM, George Zhookoff <gzhookoff@e2m.com> wrote:

> When I try to start Onan I push prime button and unit starts. But when I
> release prime button Onan stops. This is the prime circuit add on in the
> start panel.
> Any ideas?
> We're day trip to Motorcycle show in Greenville, SC.
>
_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

Report message to a moderator

Re: [GMCnet] Onan Problem [message #70282 is a reply to message #70222]

Sat, 09 January 2010 21:12

mike miller

Messages: 3576
Registered: February 2004
Location: Hillsboro, Oregon

Karma: 0

Senior Member

George Zhookoff wrote on Sat, 09 January 2010 12:46

When I try to start Onan I push prime button and unit starts. But when I release prime button Onan stops.

1st check your oil level. Then follow the troubleshooting links Ken posted.

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

Report message to a moderator

Re: [GMCnet] Onan Problem [message #70294 is a reply to message #70282]

Sat, 09 January 2010 22:28

GMCWiperMan

Messages: 1248
Registered: December 2007

Karma: 1

Senior Member

By golly, you're right, Mike, the prime switch would bypass the LOP also.
In fact, it bypasses ALL protection.

Ken H.

On Sat, Jan 9, 2010 at 10:12 PM, Mike Miller <m000035@gmail.com> wrote:

>
>
> George Zhookoff wrote on Sat, 09 January 2010 12:46
> > When I try to start Onan I push prime button and unit starts. But when I
> release prime button Onan stops.
>
>
> 1st check your oil level. Then follow the troubleshooting links Ken
> posted.
>
> --
>
_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

Report message to a moderator

Re: [GMCnet] Onan Problem [message #70319 is a reply to message #70294]

Sun, 10 January 2010 06:53

Ken Burton

Messages: 10030
Registered: January 2004
Location: Hebron, Indiana

Karma: 10

Senior Member

Several things can cause this. As mentioned before mentioned before the Low Oil Pressure switch is one of them.

I am not looking at the board diagram but from memory there around 28 - 30 volts AC generated by the ONAN for charging the Onan battery. This AC is also rectified to DC through a diode on the board and used to pick a relay to continue supplying power to the coil and fuel pump after you take you finger off of the start and prime switches. If that AC is low or missing you will have this problem. I beleve this problem can also be caused by the Onan battery charging voltage regulator.

You really need to get Duane's Onan stuff off of the GMC Western States web site to shoot this problem.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

Report message to a moderator

Previous Topic:	air conditioning
Next Topic:	Patching Holes in Roof

Goto Forum:

-=] Back to Top [=-

Current Time: Sat Oct 12 17:16:36 CDT 2024

Total time taken to generate the page: 0.01742 seconds