Home » Public Forums » GMCnet » Re: [GMCnet] Onan Issue
| Re: [GMCnet] Onan Issue [message #76336] |
Thu, 11 March 2010 14:05  |
amansfield1104
Messages: 80
Registered: August 2009
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I change spak plug and it did the same thing. So I decided to adjust the points gap since they affect timing. I got it to run better. It would pull a load but was not steady. I would miss everyones in while miss. The plugs say I still have it to rich. I adjusted the lower needle valve to get it smooth but I guess it is still a little rich. The gap on the points is about 0.038" instead of 0.020" when it runs. I guess I need to do something to get it to stop missing. Does anyone know how many degrees 0.018 point gap is?
The voltage is 129 volts under no load. It dropped to 124 volts under load of a 1500 watt heater and the rear ac unit, but it started missing. Is the 0.038 gap the is the reason the missing occurs under load?
I do not have a freq. meter to check the 60 cycle.
Art Mansfield
76 EL
On Mar 11, 2010, at 11:38 AM, amansfield1104@charter.net wrote:
> I clean my carb and seem to have messed it up. I soaked the carb in lacquer thinner. I did not take the float seat out and I guess I messed it up. The float level seemed to be messed up. I tried to reset it to the spec. The engine is running very rich. It will idle but not run under load. The plugs are black. The exhaust is black. I have taken the carb off and checked it and found nothing wrong. Float clearance was about 3/32 as shown in the manual. Set both needles to 1 1/4 turns and tried it again and it did the same thing. Turned the idle needle until it smooth out. Then tried to increase the rpm and it started to act up. I turned the power needle but it did not help. I turn it in until it quit, then I tried opening it again with no luck. The only ignition item that has not been replaced it the coil.
>
> I first did the ignition and started it up and ran ok for about 15 minutes then started to miss. Then I cleaned the carb and now it will not run but at idle.
>
> Art
> 76 EL
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| Re: [GMCnet] Onan Issue [message #76342 is a reply to message #76339] |
Thu, 11 March 2010 16:01  |
Mr ERFisher
Messages: 7117
Registered: August 2005
Karma: 2
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read through some of these articles, esp. the ones by Duane Simmons
http://gmcmotorhome.info/list.html#GEN
gene
On Thu, Mar 11, 2010 at 1:17 PM, Jay Rabe <jayrabe@hotmail.com> wrote:
>
> I'm in the process of trying to get my 6kw Onan started after sitting for
> unknown months. It turns over just fine but won't fire. Removed plugs and
> bought new and haven't put them in and tried it again yet. My manual says
> 0.025 gap.
>
> J "waiting for the rain to stop to work on it again" Rabe
> 76 Palm Beach
> Portland, OR
>
>
> > From: amansfield1104@charter.net
> > Date: Thu, 11 Mar 2010 14:05:04 -0600
> > To: gmclist@temp.gmcnet.org
> > Subject: Re: [GMCnet] Onan Issue
> >
> >
> > I change spak plug and it did the same thing. So I decided to adjust the
> points gap since they affect timing. I got it to run better. It would pull
> a load but was not steady. I would miss everyones in while miss. The plugs
> say I still have it to rich. I adjusted the lower needle valve to get it
> smooth but I guess it is still a little rich. The gap on the points is
> about 0.038" instead of 0.020" when it runs. I guess I need to do something
> to get it to stop missing. Does anyone know how many degrees 0.018 point
> gap is?
> >
> > The voltage is 129 volts under no load. It dropped to 124 volts under
> load of a 1500 watt heater and the rear ac unit, but it started missing. Is
> the 0.038 gap the is the reason the missing occurs under load?
> >
> > I do not have a freq. meter to check the 60 cycle.
> >
> > Art Mansfield
> > 76 EL
> >
> >
> > On Mar 11, 2010, at 11:38 AM, amansfield1104@charter.net wrote:
> >
> > > I clean my carb and seem to have messed it up. I soaked the carb in
> lacquer thinner. I did not take the float seat out and I guess I messed it
> up. The float level seemed to be messed up. I tried to reset it to the
> spec. The engine is running very rich. It will idle but not run under
> load. The plugs are black. The exhaust is black. I have taken the carb
> off and checked it and found nothing wrong. Float clearance was about 3/32
> as shown in the manual. Set both needles to 1 1/4 turns and tried it again
> and it did the same thing. Turned the idle needle until it smooth out.
> Then tried to increase the rpm and it started to act up. I turned the
> power needle but it did not help. I turn it in until it quit, then I tried
> opening it again with no luck. The only ignition item that has not been
> replaced it the coil.
> > >
> > > I first did the ignition and started it up and ran ok for about 15
> minutes then started to miss. Then I cleaned the carb and now it will not
> run but at idle.
> > >
> > > Art
> > > 76 EL
> > > _______________________________________________
> > > 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
>
> _________________________________________________________________
> Hotmail: Powerful Free email with security by Microsoft.
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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
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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| Re: [GMCnet] Onan Issue [message #76348 is a reply to message #76342] |
Thu, 11 March 2010 16:27 |
van.one
Messages: 70
Registered: March 2010
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Mr. Fisher:
I am a new member; was thinking of buying a 1976 GMC that was listed on
Craigslist in Oklahoma City that was in good condition, except the air-bags
on the rear were down, would not pump up. You were kind enough to send me
complete instructions as to how to replace the air-bags (with pictures).
However, I had so many emails that I had to delete them in order to make my
computer operate. Sad but true, I deleted the information which you had
sent me. If you would please send me the instructions again, this time at
my other email address, van.one@gmail.com, I will print out the instructions
and promise that I will not bother you again. Thank you very much for your
help. However, I have decided that I
am much too old (89 next May) to own a motorhome.
J. L. Vanlandingham
Norman, OK 73072
van.one@gmail.com
My other email address is <van.one@cox.net>
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| Re: [GMCnet] Onan Issue [message #76350 is a reply to message #76348] |
Thu, 11 March 2010 16:56 |
amansfield1104
Messages: 80
Registered: August 2009
Karma: 0
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I checked the oil and added some. I played with the gap and the power needle valve and to it run better but it still was acting up some. It is a 6 KW.
I guess the next thing is to check the valve lash but I am not sure where to start to check the valve lash.
Art
Decatur AL
76 EL
On Mar 11, 2010, at 4:27 PM, J. Leon Van landingham wrote:
> Mr. Fisher:
>
> I am a new member; was thinking of buying a 1976 GMC that was listed on
> Craigslist in Oklahoma City that was in good condition, except the air-bags
> on the rear were down, would not pump up. You were kind enough to send me
> complete instructions as to how to replace the air-bags (with pictures).
> However, I had so many emails that I had to delete them in order to make my
> computer operate. Sad but true, I deleted the information which you had
> sent me. If you would please send me the instructions again, this time at
> my other email address, van.one@gmail.com, I will print out the instructions
> and promise that I will not bother you again. Thank you very much for your
> help. However, I have decided that I
> am much too old (89 next May) to own a motorhome.
>
> J. L. Vanlandingham
> Norman, OK 73072
> van.one@gmail.com
>
> My other email address is <van.one@cox.net>
>
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
_______________________________________________
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| Re: [GMCnet] Onan Issue [message #76355 is a reply to message #76348] |
Thu, 11 March 2010 17:19 |
 |
USAussie
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
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J. Leon,
A wise decision!
Hope you celebrate a Happy 89th. birthday in May and many more thereafter!
All the best,
Rob Mueller
Sydney, Australia
AUS '75 Avion-The Blue Streak TZE365V100428
USA '75 Avion-Double Trouble TZE365V100426
-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of J. Leon Van landingham
Sent: Friday, 12 March 2010 9:27 AM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] Onan Issue
However, I have decided that I am much too old (89 next May) to own a
motorhome.
J. L. Vanlandingham
Norman, OK 73072
van.one@gmail.com
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Regards,
Rob M. (USAussie)
The Pedantic Mechanic
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
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| Re: [GMCnet] Onan Issue [message #76367 is a reply to message #76336] |
Thu, 11 March 2010 20:18 |
C Boyd
Messages: 2629
Registered: April 2006
Karma: 18
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Senior Member |
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Does anyone know how many degrees 0.018 point gap is?
Art Mansfield
76 EL
Sir: 28*-30* IIRC?
C. Boyd
76 Crestmont
East Tennessee
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| Re: [GMCnet] Onan Issue [message #76388 is a reply to message #76336] |
Thu, 11 March 2010 22:41 |
JohnL455
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
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Senior Member |
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Can't you just scan it with the OBDII reader and the the codes will tell you what to replace?
Sorry, in a wacky mood.
wrong century
Seriously by the sound of the miss you should be able to 'Old School' tell a few things. If it's an even continuous miss that would point to a cylinder with most likely a spark issue, but it could be a mechanical issue on that side. If it's an eratic miss it could be mixture or a faulty coil or connection as mentioned.
Make sure all the "obvious" stuff is ruled out. Is the choke wide open and staying wide open? If it's hunting it could be the carb or govenor adjustment is off. Make sure the air filter didn't get oil on it and restricted. Make sure the wires don't have "green stuff" growing on both ends. (though is is St. Patty's day soon) Spare parts are nice to have to say substitute coils. Check the connections to the coil and other ignition parts and make sure the crimps are all good.
John Lebetski
Woodstock, IL
77 Eleganza II
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| Re: [GMCnet] Onan Issue [message #76389 is a reply to message #76388] |
Thu, 11 March 2010 23:00 |
jimk
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
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Senior Member |
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If you gap a standard point smaller, it will run better for a short
time then burn the points.
Try our solid state system using Onan parts, it will out perform any
other unit as the Dwell angle is almost doubled.
On Thu, Mar 11, 2010 at 8:41 PM, John R. Lebetski <gransport@aol.com> wrote:
>
>
> Can't you just scan it with the OBDII reader and the the codes will tell you what to replace?
> Sorry, in a wacky mood.
> wrong century
> Seriously by the sound of the miss you should be able to 'Old School' tell a few things. Â If it's an even continuous miss that would point to a cylinder with most likely a spark issue, but it could be a mechanical issue on that side. If it's an eratic miss it could be mixture or a faulty coil or connection as mentioned.
> Make sure all the "obvious" stuff is ruled out. Is the choke wide open and staying wide open? If it's hunting it could be the carb or govenor adjustment is off. Make sure the air filter didn't get oil on it and restricted. Make sure the wires don't have "green stuff" growing on both ends. (though is is St. Patty's day soon) Spare parts are nice to have to say substitute coils. Check the connections to the coil and other ignition parts and make sure the crimps are all good.
> --
> John Lebetski
> Chicago, IL
> 77 Eleganza II
> _______________________________________________
> GMCnet mailing list
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--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
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| Re: [GMCnet] Onan Issue [message #76400 is a reply to message #76350] |
Fri, 12 March 2010 06:08 |
Steven Ferguson
Messages: 3447
Registered: May 2006
Karma: 0
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Senior Member |
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Art,
Back to basics here. If it ran fine before you cleaned the carb, and
doesn't now, why bother with the valves? I always try to go back to
the last thing I touched.
On Thu, Mar 11, 2010 at 3:56 PM, amansfield1104@charter.net
<amansfield1104@charter.net> wrote:
> I checked the oil and added some. I played with the gap and the power needle valve and to it run better but it still was acting up some. It is a 6 KW.
>
> I guess the next thing is to check the valve lash but I am not sure where to start to check the valve lash.
>
> Art
> Decatur AL
> 76 EL
>
> On Mar 11, 2010, at 4:27 PM, J. Leon Van landingham wrote:
>
>> Mr. Fisher:
>>
>> I am a new member; was thinking of buying a 1976 GMC that was listed on
>> Craigslist in Oklahoma City that was in good condition, except the air-bags
>> on the rear were down, would not pump up. You were kind enough to send me
>> complete instructions as to how to replace the air-bags (with pictures).
>> However, I had so many emails that I had to delete them in order to make my
>> computer operate. Sad but true, I deleted the information which you had
>> sent me. If you would please send me the instructions again, this time at
>> my other email address, van.one@gmail.com, I will print out the instructions
>> and promise that I will not bother you again. Thank you very much for your
>> help. However, I have decided that I
>> am much too old (89 next May) to own a motorhome.
>>
>> J. L. Vanlandingham
>> Norman, OK 73072
>> van.one@gmail.com
>>
>> My other email address is <van.one@cox.net>
>>
>> _______________________________________________
>> 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/
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| Re: [GMCnet] Onan Issue [message #76424 is a reply to message #76400] |
Fri, 12 March 2010 10:10 |
amansfield1104
Messages: 80
Registered: August 2009
Karma: 0
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Member |
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Thanks everybody. If I had another coil I would try it. My trouble started last summer hen it quit on trip. hen I go home changed the plugs and it seemed to run ok. Just before I left for Lazdays I checked checked the generator out and found a gas leak so I did not use it. When I got back home I worked on it. I found it would not run to well after I tighten the fuel line and checked the plugs and compression (125psi). It was running very rough so I checked the points and they were burnt. I cleaned then and adjusted them while it was running. It ran ok for a while then started acting up. I then decided to replace the wires, plugs, points and clean the carb. I was going to replace the condenser but the one sent was the wrong one. I could get it started and it would idle but not run. The points were set to about 0.020". Then I change the gap while it was running and it smooth out. So I guess the timing is off some. It still miss once in while under load. And y
es the points will not last as long when running a larger gap so the timing need to be reset.
So now I see three things to do:
1) Reset the timing (don't think it will help until the points burn)
2) Reset the valve lash (Could be off but doubt that will fix the problem since it is not noise)
3) Remove the head and clean ( Carbon build up in the head cold cause a problem hour meter is broken at 650 hours)
4) Replace the coil (could be weak and could cause problem)
5) Replace the carb or have the throttle butterfly shaft redone since it has worn and leaks (cold be an issue since the governor is always adjusting the and may change the leak rate but I doubt it)
Question can the timing slip?
Art
On Mar 12, 2010, at 6:08 AM, Steven Ferguson wrote:
> Art,
> Back to basics here. If it ran fine before you cleaned the carb, and
> doesn't now, why bother with the valves? I always try to go back to
> the last thing I touched.
>
> On Thu, Mar 11, 2010 at 3:56 PM, amansfield1104@charter.net
> <amansfield1104@charter.net> wrote:
>> I checked the oil and added some. I played with the gap and the power needle valve and to it run better but it still was acting up some. It is a 6 KW.
>>
>> I guess the next thing is to check the valve lash but I am not sure where to start to check the valve lash.
>>
>> Art
>> Decatur AL
>> 76 EL
>>
>> On Mar 11, 2010, at 4:27 PM, J. Leon Van landingham wrote:
>>
>>> Mr. Fisher:
>>>
>>> I am a new member; was thinking of buying a 1976 GMC that was listed on
>>> Craigslist in Oklahoma City that was in good condition, except the air-bags
>>> on the rear were down, would not pump up. You were kind enough to send me
>>> complete instructions as to how to replace the air-bags (with pictures).
>>> However, I had so many emails that I had to delete them in order to make my
>>> computer operate. Sad but true, I deleted the information which you had
>>> sent me. If you would please send me the instructions again, this time at
>>> my other email address, van.one@gmail.com, I will print out the instructions
>>> and promise that I will not bother you again. Thank you very much for your
>>> help. However, I have decided that I
>>> am much too old (89 next May) to own a motorhome.
>>>
>>> J. L. Vanlandingham
>>> Norman, OK 73072
>>> van.one@gmail.com
>>>
>>> My other email address is <van.one@cox.net>
>>>
>>> _______________________________________________
>>> 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
_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
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| Re: [GMCnet] Onan Issue [message #76438 is a reply to message #76424] |
Fri, 12 March 2010 11:53 |
Steven Ferguson
Messages: 3447
Registered: May 2006
Karma: 0
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Senior Member |
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If you remove the heads for decarboning, use a medium such as glass
beads. You can reuse the old head gasket, just apply several coats of
silver paint to each side. They will be fine to reuse if you do this.
On Fri, Mar 12, 2010 at 9:10 AM, amansfield1104@charter.net
<amansfield1104@charter.net> wrote:
> Thanks everybody. If I had another coil I would try it. My trouble started last summer hen it quit on trip. hen I go home changed the plugs and it seemed to run ok. Just before I left for Lazdays I checked checked the generator out and found a gas leak so I did not use it. When I got back home I worked on it. I found it would not run to well after I tighten the fuel line and checked the plugs and compression (125psi). It was running very rough so I checked the points and they were burnt. I cleaned then and adjusted them while it was running. It ran ok for a while then started acting up. I then decided to replace the wires, plugs, points and clean the carb. I was going to replace the condenser but the one sent was the wrong one. I could get it started and it would idle but not run. The points were set to about 0.020". Then I change the gap while it was running and it smooth out. So I guess the timing is off some. It still miss once in while under load. And y
> es the points will not last as long when running a larger gap so the timing need to be reset.
>
> So now I see three things to do:
> 1) Reset the timing (don't think it will help until the points burn)
> 2) Reset the valve lash (Could be off but doubt that will fix the problem since it is not noise)
> 3) Remove the head and clean ( Carbon build up in the head cold cause a problem hour meter is broken at 650 hours)
> 4) Replace the coil (could be weak and could cause problem)
> 5) Replace the carb or have the throttle butterfly shaft redone since it has worn and leaks (cold be an issue since the governor is always adjusting the and may change the leak rate but I doubt it)
>
> Question can the timing slip?
>
> Art
>
>
> On Mar 12, 2010, at 6:08 AM, Steven Ferguson wrote:
>
>> Art,
>> Back to basics here. If it ran fine before you cleaned the carb, and
>> doesn't now, why bother with the valves? I always try to go back to
>> the last thing I touched.
>>
>> On Thu, Mar 11, 2010 at 3:56 PM, amansfield1104@charter.net
>> <amansfield1104@charter.net> wrote:
>>> I checked the oil and added some. I played with the gap and the power needle valve and to it run better but it still was acting up some. It is a 6 KW.
>>>
>>> I guess the next thing is to check the valve lash but I am not sure where to start to check the valve lash.
>>>
>>> Art
>>> Decatur AL
>>> 76 EL
>>>
>>> On Mar 11, 2010, at 4:27 PM, J. Leon Van landingham wrote:
>>>
>>>> Mr. Fisher:
>>>>
>>>> I am a new member; was thinking of buying a 1976 GMC that was listed on
>>>> Craigslist in Oklahoma City that was in good condition, except the air-bags
>>>> on the rear were down, would not pump up. You were kind enough to send me
>>>> complete instructions as to how to replace the air-bags (with pictures).
>>>> However, I had so many emails that I had to delete them in order to make my
>>>> computer operate. Sad but true, I deleted the information which you had
>>>> sent me. If you would please send me the instructions again, this time at
>>>> my other email address, van.one@gmail.com, I will print out the instructions
>>>> and promise that I will not bother you again. Thank you very much for your
>>>> help. However, I have decided that I
>>>> am much too old (89 next May) to own a motorhome.
>>>>
>>>> J. L. Vanlandingham
>>>> Norman, OK 73072
>>>> van.one@gmail.com
>>>>
>>>> My other email address is <van.one@cox.net>
>>>>
>>>> _______________________________________________
>>>> 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
>
> _______________________________________________
> 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
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| Re: [GMCnet] Onan Issue [message #76450 is a reply to message #76424] |
Fri, 12 March 2010 12:44 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
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Senior Member |
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| amansfield1104 wrote on Fri, 12 March 2010 10:10 |
Thanks everybody. If I had another coil I would try it. My trouble started last summer hen it quit on trip. hen I go home changed the plugs and it seemed to run ok. Just before I left for Lazdays I checked checked the generator out and found a gas leak so I did not use it. When I got back home I worked on it. I found it would not run to well after I tighten the fuel line and checked the plugs and compression (125psi). It was running very rough so I checked the points and they were burnt. I cleaned then and adjusted them while it was running. It ran ok for a while then started acting up. I then decided to replace the wires, plugs, points and clean the carb. I was going to replace the condenser but the one sent was the wrong one. I could get it started and it would idle but not run. The points were set to about 0.020". Then I change the gap while it was running and it smooth out. So I guess the timing is off some. It still miss once in while under load. And y
es the points will not last as long when running a larger gap so the timing need to be reset.
So now I see three things to do:
1) Reset the timing (don't think it will help until the points burn)
2) Reset the valve lash (Could be off but doubt that will fix the problem since it is not noise)
3) Remove the head and clean ( Carbon build up in the head cold cause a problem hour meter is broken at 650 hours)
4) Replace the coil (could be weak and could cause problem)
5) Replace the carb or have the throttle butterfly shaft redone since it has worn and leaks (cold be an issue since the governor is always adjusting the and may change the leak rate but I doubt it)
Question can the timing slip?
Art
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Why don't you just throw a timing light on it and see what you have. Do not be surprised when you see it jumping all around. The Onan mechanical setup for opening those points is a a real kludge. You will just have to average out what you see.
This why many of us went to the Pertronix electronic pick up / electronic ignition that Lawrence Gaskins developed. I installed it a few years back and never have had to worry about points wear or timing again.
Ken H. put up a photo album on it.
http://www.gmcmhphotos.com/photos/showphoto.php?photo=6785&cat=3608
I did not remove the bracket off of the pick up. I just bent it and mounted it. Also in initially mounted it with double faced tape and a small set of vice grips. I ran it to check the timing and adjusted it's position until I got 26 BTDC. Then I drilled a pair of holes and mounted it permanently. I also ran an additional ground wire from it back to the engine by the coil.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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| Re: [GMCnet] Onan Issue [message #76454 is a reply to message #76450] |
Fri, 12 March 2010 13:00 |
amansfield1104
Messages: 80
Registered: August 2009
Karma: 0
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Member |
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Thanks everyone
On Mar 12, 2010, at 12:44 PM, Ken Burton wrote:
>
>
> amansfield1104 wrote on Fri, 12 March 2010 10:10
>> Thanks everybody. If I had another coil I would try it. My trouble started last summer hen it quit on trip. hen I go home changed the plugs and it seemed to run ok. Just before I left for Lazdays I checked checked the generator out and found a gas leak so I did not use it. When I got back home I worked on it. I found it would not run to well after I tighten the fuel line and checked the plugs and compression (125psi). It was running very rough so I checked the points and they were burnt. I cleaned then and adjusted them while it was running. It ran ok for a while then started acting up. I then decided to replace the wires, plugs, points and clean the carb. I was going to replace the condenser but the one sent was the wrong one. I could get it started and it would idle but not run. The points were set to about 0.020". Then I change the gap while it was running and it smooth out. So I guess the timing is off some. It still miss once in while under load. An
d
> y
>> es the points will not last as long when running a larger gap so the timing need to be reset.
>>
>> So now I see three things to do:
>> 1) Reset the timing (don't think it will help until the points burn)
>> 2) Reset the valve lash (Could be off but doubt that will fix the problem since it is not noise)
>> 3) Remove the head and clean ( Carbon build up in the head cold cause a problem hour meter is broken at 650 hours)
>> 4) Replace the coil (could be weak and could cause problem)
>> 5) Replace the carb or have the throttle butterfly shaft redone since it has worn and leaks (cold be an issue since the governor is always adjusting the and may change the leak rate but I doubt it)
>>
>> Question can the timing slip?
>>
>> Art
>
>
> Why don't you just throw a timing light on it and see what you have. Do not be surprised when you see it jumping all around. The Onan mechanical setup for opening those points is a a real kludge. You will just have to average out what you see.
>
> This why many of us went to the Pertronix electronic pick up / electronic ignition that Lawrence Gaskins developed. I installed it a few years back and never have had to worry about points wear or timing again.
>
> Ken H. put up a photo album on it.
>
> http://www.gmcmhphotos.com/photos/showphoto.php?photo=6785&cat=3608
>
> I did not remove the bracket off of the pick up. I just bent it and mounted it. Also in initially mounted it with double faced tape and a small set of vice grips. I ran it to check the timing and adjusted it's position until I got 26 BTDC. Then I drilled a pair of holes and mounted it permanently. I also ran an additional ground wire from it back to the engine by the coil.
>
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
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