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My Onan runs like Sheet: Episode III, WTF is wrong with this thing!? [message #81937] Mon, 26 April 2010 11:19 Go to next message
Duce Apocalypse is currently offline  Duce Apocalypse   United States
Messages: 824
Registered: May 2009
Location: Los angeles
Karma: 0
Senior Member

Well, here is my latest installment of the ongoing saga of trying to get my green turd, which formerly performed flawlessly to again run properly.


Well taking the advice of many here I decarbonized the heads on the Onan, without a bead blasting cabinent this takes a couple hours to soak the heads in carby dip and scrub, and scrape the hardened crap off the heads, and recondition the gaskets for reuse.

Upon reinstalling the heads I fired up the onan, and adjusted the carb. It ran better, but still stumbled and stammered occationally...


Saturday I received another coil and carb from Michael at GMCRecs for trouble shooting purposes. I installed the other coil and performance did improve some, but still no dice as to eliminating the wandering stumble. so I tried the carb, again no change, but at least I eliminated these as causes. with the new coil the Onan still emits its EM feild so I'm wondering if this is just normal for the Onan? maybe if someone else who has a DMM can try to test a running onan can tell me if their unit starts acting strangely...

I pulled the points, and check them, regapped them, and reinstalled. this time the onan ran fine for 20 minutes. I shut it down to finanlize some other stuff and when I restarted the onan again it started stumbling and stammering like before.

finally I noticed I was having trouble getting it started and the start switch seemed to not function. so I yanked the covers on the relays on the control board, it sems they are having problems functioning correctly after some messing around with the contacts I finally got it to fire up again. At this point I should mention that in previous tests I had hotwired the control board with the 9-11 jumper to eliminate the board compleatly.

Im beginning to think the relays may be geting faulty on my board, would this cause the engine to intermittently stumble and stammer?

I'm wondering also if there is maybe something mechanical I missed in the engine itself? im thinking maybe valve tappets need adjusting? how hard is that to do?






73 Canyon Lands, (a.k.a. The Yellow Submarine) West Los Angeles CA

[Updated on: Mon, 26 April 2010 11:19]

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Re: [GMCnet] My Onan runs like Sheet: Episode III, WTF is wrong with this thing!? [message #82070 is a reply to message #81937] Tue, 27 April 2010 08:53 Go to previous messageGo to next message
Steven Ferguson is currently offline  Steven Ferguson   United States
Messages: 3447
Registered: May 2006
Karma: 0
Senior Member
Shan,
Duane charges $100 plus your old board for one of his upgraded, OEM
boards. It is a darn good deal. If you are having trouble contacting
him I have one of his boards that I have not installed and I can send
it to you but you must replace it at your earliest.

On Mon, Apr 26, 2010 at 9:19 AM, Shan Rose <defconfx@gmail.com> wrote:
>
>
> Well, here is my latest installment of the ongoing saga of trying to get my green turd, which formerly pweformed flawlessly to again run properly.
>
>
> Well taking the advice of many here I decarbonized the heads on the Onan, without a bead blasting cabinent this takes a couple hours to soak the heads in carby dip and scrub, and scrape the hardened crap off the heads, and recondition the gaskets for reuse.
>
> Upon reinstalling the heads I fired up the onan, and adjusted the carb. It ran better, but still stumbled and stammered occationally...
>
>
> Saturday I received another coil and carb from Michael at GMCRecs for trouble shooting purposes. I installed the other coil and performance did improve some, but still no dice as to eliminating the wandering stumble. so I tried the carb, again no change, but at least I eliminated these as causes. with the new coil the Onan still emits its EM feild so I'm wondering if this is just normal for the Onan? maybe if someone else who has a DMM can try to test a running onan can tell me if their unit starts acting strangely...
>
> I pulled the points, and check them, regapped them, and reinstalled. this time the onan ran fine for 20 minutes. I shut it down to finanlize some other stuff and when I restarted the onan again it started stumbling and stammering like before.
>
> finally I noticed I was having trouble getting it started and the start switch seemed to not function. so I yanked the covers on the relays on the control board, it sems they are having problems functioning correctly after some messing around with the contacts I finally got it to fire up again. At this point I should mention that in previous tests I had hotwired the control board with the 9-11 jumper to eliminate the board compleatly.
>
> Im beginning to think the relays may be geting faulty on my board, would this cause the engine to intermittently stumble and stammer?
>
> I'm wondering also if there is maybe something mechanical I missed in the engine itself? im thinking maybe valve tappets need adjusting? how hard is that to do?
>
>
>
>
>
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Steve Ferguson
'76 EII
Sierra Vista, AZ
Urethane bushing source
www.bdub.net/ferguson/
_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

Re: My Onan runs like Sheet: Episode III, WTF is wrong with this thing!? [message #82144 is a reply to message #81937] Tue, 27 April 2010 17:16 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma: 7
Senior Member
Shan,

I sorry if you covered this, but when was the valve lash set last?

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: My Onan runs like Sheet: Episode III, WTF is wrong with this thing!? [message #82259 is a reply to message #82144] Wed, 28 April 2010 11:02 Go to previous messageGo to next message
Duce Apocalypse is currently offline  Duce Apocalypse   United States
Messages: 824
Registered: May 2009
Location: Los angeles
Karma: 0
Senior Member

thats a good question, looking at the onan I'd say at the factory most likely...


mcolie wrote on Tue, 27 April 2010 17:16

Shan,

I sorry if you covered this, but when was the valve lash set last?

Matt



73 Canyon Lands, (a.k.a. The Yellow Submarine) West Los Angeles CA
Re: [GMCnet] My Onan runs like Sheet: Episode III, WTF is wrong with this thing!? [message #82264 is a reply to message #82070] Wed, 28 April 2010 11:32 Go to previous messageGo to next message
Duce Apocalypse is currently offline  Duce Apocalypse   United States
Messages: 824
Registered: May 2009
Location: Los angeles
Karma: 0
Senior Member

I might just take you up on that offer Steve, I tried to send you a PM but it said you are not accepting them. what does Duane update on the boards exactly?

Steven Ferguson wrote on Tue, 27 April 2010 08:53

Shan,
Duane charges $100 plus your old board for one of his upgraded, OEM
boards. It is a darn good deal. If you are having trouble contacting
him I have one of his boards that I have not installed and I can send
it to you but you must replace it at your earliest.

On Mon, Apr 26, 2010 at 9:19 AM, Shan Rose <defconfx@gmail.com> wrote:
>
>
> Well, here is my latest installment of the ongoing saga of trying to get my green turd, which formerly pweformed flawlessly to again run properly.
>
>
> Well taking the advice of many here I decarbonized the heads on the Onan, without a bead blasting cabinent this takes a couple hours to soak the heads in carby dip and scrub, and scrape the hardened crap off the heads, and recondition the gaskets for reuse.
>
> Upon reinstalling the heads I fired up the onan, and adjusted the carb. It ran better, but still stumbled and stammered occationally...
>
>
> Saturday I received another coil and carb from Michael at GMCRecs for trouble shooting purposes. I installed the other coil and performance did improve some, but still no dice as to eliminating the wandering stumble. so I tried the carb, again no change, but at least I eliminated these as causes. with the new coil the Onan still emits its EM feild so I'm wondering if this is just normal for the Onan? maybe if someone else who has a DMM can try to test a running onan can tell me if their unit starts acting strangely...
>
> I pulled the points, and check them, regapped them, and reinstalled. this time the onan ran fine for 20 minutes. I shut it down to finanlize some other stuff and when I restarted the onan again it started stumbling and stammering like before.
>
> finally I noticed I was having trouble getting it started and the start switch seemed to not function. so I yanked the covers on the relays on the control board, it sems they are having problems functioning correctly after some messing around with the contacts I finally got it to fire up again. At this point I should mention that in previous tests I had hotwired the control board with the 9-11 jumper to eliminate the board compleatly.
>
> Im beginning to think the relays may be geting faulty on my board, would this cause the engine to intermittently stumble and stammer?
>
> I'm wondering also if there is maybe something mechanical I missed in the engine itself? im thinking maybe valve tappets need adjusting? how hard is that to do?
>
>
>
>
>
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Steve Ferguson
'76 EII
Sierra Vista, AZ
Urethane bushing source
www.bdub.net/ferguson/
_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist





73 Canyon Lands, (a.k.a. The Yellow Submarine) West Los Angeles CA
Re: [GMCnet] My Onan runs like Sheet: Episode III, WTF is wrong with this thing!? [message #82329 is a reply to message #82264] Wed, 28 April 2010 18:01 Go to previous message
Steven Ferguson is currently offline  Steven Ferguson   United States
Messages: 3447
Registered: May 2006
Karma: 0
Senior Member
I think he replaced all of the outdated components with state of the
art ones. Relays, etc. I'll add your address to my book and you
should be able to get through.
Otherwise, botiemad11@juno.com should work

On Wed, Apr 28, 2010 at 9:32 AM, Shan Rose <defconfx@gmail.com> wrote:
>
>
> I might just take you up on that offer Steve, I tried to send you a PM but it said you are not accepting them. what does Duane update on the boards exactly?
>
> Steven Ferguson wrote on Tue, 27 April 2010 08&#58;53
>> Shan,
>>  Duane charges $100 plus your old board for one of his upgraded, OEM
>> boards.  It is a darn good deal.  If you are having trouble contacting
>> him I have one of his boards that I have not installed and I can send
>> it to you but you must replace it at your earliest.
>>
>> On Mon, Apr 26, 2010 at 9:19 AM, Shan Rose <defconfx@gmail.com> wrote:
>> >
>> >
>> > Well, here is my latest installment of the ongoing saga of trying to get my green turd, which formerly pweformed flawlessly to again run properly.
>> >
>> >
>> > Well taking the advice of many here I decarbonized the heads on the Onan, without a bead blasting cabinent this takes a couple hours to soak the heads in carby dip and scrub, and scrape the hardened crap off the heads, and recondition the gaskets for reuse.
>> >
>> > Upon reinstalling the heads I fired up the onan, and adjusted the carb. It ran better, but still stumbled and stammered occationally...
>> >
>> >
>> > Saturday I received another coil and carb from Michael at GMCRecs for trouble shooting purposes. I installed the other coil and performance did improve some, but still no dice as to eliminating the wandering stumble. so I tried the carb, again no change, but at least I eliminated these as causes. with the new coil the Onan still emits its EM feild so I'm wondering if this is just normal for the Onan? maybe if someone else who has a DMM can try to test a running onan can tell me if their unit starts acting strangely...
>> >
>> > I pulled the points, and check them, regapped them, and reinstalled. this time the onan ran fine for 20 minutes. I shut it down to finanlize some other stuff and when I restarted the onan again it started stumbling and stammering like before.
>> >
>> > finally I noticed I was having trouble getting it started and the start switch seemed to not function. so I yanked the covers on the relays on the control board, it sems they are having problems functioning correctly after some messing around with the contacts I finally got it to fire up again. At this point I should mention that in previous tests I had hotwired the control board with the 9-11 jumper to eliminate the board compleatly.
>> >
>> > Im beginning to think the relays may be geting faulty on my board, would this cause the engine to intermittently stumble and stammer?
>> >
>> > I'm wondering also if there is maybe something mechanical I missed in the engine itself? im thinking maybe valve tappets need adjusting? how hard is that to do?
>> >
>> >
>> >
>> >
>> >
>> > _______________________________________________
>> > GMCnet mailing list
>> > List Information and Subscription Options:
>> > http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>> >
>>
>>
>>
>> --
>> Steve Ferguson
>> '76 EII
>> Sierra Vista, AZ
>> Urethane bushing source
>> www.bdub.net/ferguson/
>> _______________________________________________
>> GMCnet mailing list
>> List Information and Subscription Options:
>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
>
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Steve Ferguson
'76 EII
Sierra Vista, AZ
Urethane bushing source
www.bdub.net/ferguson/
_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

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