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[GMCnet] Surging Onan [message #164064] Sat, 24 March 2012 15:41 Go to next message
jhbridges is currently offline  jhbridges   United States
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Registered: May 2011
Location: Braselton ga
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Senior Member
Friend who has SOB (some other breed) dogs and drives an SOB coach is having genset problems.  It's a 4KW 'Microlite' which is a two pole alternator single cylinder set.  New fuel lines, sparking plug, and auir filter.  Problem is, the set surges - rather more than it should.  Runs and takes load OK once it's warm, but if it coughs, it will surge before settling.  At times, it surges so much it drops off line.  I can find no loose wires.  The linkage appeares unworn, and hasn't any place where it's binding. 
Anyone got a URL for The Book on this toy?  Or, can anyone tell me, is there a servo gain control on the controller someplace?  It's mounted such that it's not gonna be easy to get to whatever electronics are in it.  Model # 4KYFA26100G S/N 19737402781.
 
Thanks,
 
Johnny
 
'76 23' transmode norris
'76 palm beach
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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
Re: [GMCnet] Surging Onan [message #164065 is a reply to message #164064] Sat, 24 March 2012 15:59 Go to previous messageGo to next message
Bob de Kruyff   United States
Messages: 4260
Registered: January 2004
Location: Chandler, AZ
Karma: 1
Senior Member
Johnny Bridges wrote on Sat, 24 March 2012 14:41

Friend who has SOB (some other breed) dogs and drives an SOB coach is having genset problems.  It's a 4KW 'Microlite' which is a two pole alternator single cylinder set.  New fuel lines, sparking plug, and auir filter.  Problem is, the set surges - rather more than it should.  Runs and takes load OK once it's warm, but if it coughs, it will surge before settling.  At times, it surges so much it drops off line.  I can find no loose wires.  The linkage appeares unworn, and hasn't any place where it's binding. 
Anyone got a URL for The Book on this toy?  Or, can anyone tell me, is there a servo gain control on the controller someplace?  It's mounted such that it's not gonna be easy to get to whatever electronics are in it.  Model # 4KYFA26100G S/N 19737402781.
 
Thanks,
 
Johnny
 
'76 23' transmode norris
'76 palm beach
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Running too lean. The main jet may have a plastic knob that can be set for altitude, depending on the year. If it has one, make sure it is turned to the "left" If not, the mixture screw may be on the side, just above the float bowl. I would turn it out a half turn.


Bob de Kruyff
78 Eleganza
Chandler, AZ
Re: [GMCnet] Surging Onan [message #164068 is a reply to message #164064] Sat, 24 March 2012 16:59 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Registered: October 2006
Location: Woodstock, IL
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I agree ---too lean or is there a sensitivy adj on the governor as on our Power Drawer series?

John Lebetski
Woodstock, IL
77 Eleganza II
Re: [GMCnet] Surging Onan [message #164092 is a reply to message #164068] Sat, 24 March 2012 20:10 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
Messages: 8412
Registered: May 2011
Location: Braselton ga
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Senior Member
Haven't found a sensitivity (what I called 'loop gain') control, but I don't yet have the repair manual for the set.  If it were running lean, I'd expect it to overheat which it isn't.  But I'll try a bit richer and see if that helps.
 
--johnny
 
'76 23' transmode norris
'76 palm beach
 

From: John R. Lebetski <gransport@aol.com>
To: gmclist@temp.gmcnet.org
Sent: Saturday, March 24, 2012 5:59 PM
Subject: Re: [GMCnet] Surging Onan



I agree ---too lean or is there a sensitivy adj on the governor as on our Power Drawer series?
--
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
Re: [GMCnet] Surging Onan [message #164103 is a reply to message #164092] Sat, 24 March 2012 21:17 Go to previous messageGo to next message
Bob de Kruyff   United States
Messages: 4260
Registered: January 2004
Location: Chandler, AZ
Karma: 1
Senior Member
Johnny Bridges wrote on Sat, 24 March 2012 19:10

Haven't found a sensitivity (what I called 'loop gain') control, but I don't yet have the repair manual for the set.  If it were running lean, I'd expect it to overheat which it isn't.  But I'll try a bit richer and see if that helps.
 
--johnny
 
'76 23' transmode norris
'76 palm beach
 

From: John R. Lebetski <gransport@aol.com>
To: gmclist@temp.gmcnet.org
Sent: Saturday, March 24, 2012 5:59 PM
Subject: Re: [GMCnet] Surging Onan



I agree ---too lean or is there a sensitivy adj on the governor as on our Power Drawer series?
--
John Lebetski
Chicago, IL
77 Eleganza II
Source America First
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Normally it wouldn't overheat with a slight lean setting--anyway, how would you know?


Bob de Kruyff
78 Eleganza
Chandler, AZ
Re: [GMCnet] Surging Onan [message #164137 is a reply to message #164092] Sun, 25 March 2012 09:54 Go to previous messageGo to next message
mickeysss is currently offline  mickeysss   United States
Messages: 1476
Registered: January 2012
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Senior Member
you need the CD from the group here of Duane Simmons who past away recently, he was a great gmc god.

now has risen to be the onan and gmc motor home hall of fame. i only got to talk to him once on the phone and

he invited me over to his house when i was ready and left me giggling with kindness and the fun of the gmc kind.

very big loss for all of us. god bless him for ever. humbly. I have to go over the CD as well again mine will not start

and i have full gas so it is not low on fuel. I think you start with the fuel line off in a bucket to see if the pump is working

then - well the CD shows you ever thing, it is great, try and get it from PO Box 4535 River side ca 92514

pphone number 909 792 3320 Mr. Maki A must have if you have an onan. I for got the price but it is worth its weight in gold.

On Mar 24, 2012, at 6:10 PM, Johnny Bridges wrote:

> Haven't found a sensitivity (what I called 'loop gain') control, but I don't yet have the repair manual for the set. If it were running lean, I'd expect it to overheat which it isn't. But I'll try a bit richer and see if that helps.
>
> --johnny
>
> '76 23' transmode norris
> '76 palm beach
>
>
> From: John R. Lebetski <gransport@aol.com>
> To: gmclist@temp.gmcnet.org
> Sent: Saturday, March 24, 2012 5:59 PM
> Subject: Re: [GMCnet] Surging Onan
>
>
>
> I agree ---too lean or is there a sensitivy adj on the governor as on our Power Drawer series?
> --
> John Lebetski
> Chicago, IL
> 77 Eleganza II
> Source America First
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> _______________________________________________
> GMCnet mailing list
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Re: [GMCnet] Surging Onan [message #164144 is a reply to message #164137] Sun, 25 March 2012 12:43 Go to previous message
jhbridges is currently offline  jhbridges   United States
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
Senior Member
We got it kicking aropund the office someplace.  The 4 pole Onans gave relatively little trouble, but the EPA finally urinated all over manufacturing the (flat head) engines they used.  And the flat heads in most other service as well.  Mostly as a cost concern I suspect, when Onan went to OHV engines, even the 4 pole ones spin faster (2400 RPM).  The 2 poles, like this one, run 3600RPM.  Cheaper to build, but nnot nearly as robust.  They're also noisier, ansd require less hysteresis in the engine control because there's less rotating mass, hence a faster sag with load increase.  This one suffers from that last.  I'm gonna try riching it up a bit,  Failing that I will prolly have to yank the thing outa the coach. 
 
--johnny
'76 23' transmode norris with a Junkerac
'76 palm beach with a 6KW Onan flathead twin

From: mickey's space ship shuttle <mickeysss@me.com>
To: gmclist@temp.gmcnet.org
Sent: Sunday, March 25, 2012 10:54 AM
Subject: Re: [GMCnet] Surging Onan

you need the CD from the group here of Duane Simmons who past away recently, he was a great gmc god.

now has risen to be the onan and gmc motor home hall of fame. i only got to talk to him once on the phone and

he invited me over to his house when i was ready and left me giggling with kindness and the fun of the gmc kind.

very big loss for all of us. god bless him for ever. humbly. I have to go over the CD as well again mine will not start

and i have full gas so it is not low on fuel. I think you start with the fuel line off in a bucket to see if the pump is working

then - well the CD shows you ever thing, it is great, try and get it from PO Box 4535 River side ca 92514

pphone number 909 792 3320 Mr. Maki  A must have if you have an onan. I for got the price but it is worth its weight in gold. 

On Mar 24, 2012, at 6:10 PM, Johnny Bridges wrote:

> Haven't found a sensitivity (what I called 'loop gain') control, but I don't yet have the repair manual for the set.  If it were running lean, I'd expect it to overheat which it isn't.  But I'll try a bit richer and see if that helps.

> --johnny

> '76 23' transmode norris
> '76 palm beach

>
> From: John R. Lebetski <gransport@aol.com>
> To: gmclist@temp.gmcnet.org
> Sent: Saturday, March 24, 2012 5:59 PM
> Subject: Re: [GMCnet] Surging Onan
>
>
>
> I agree ---too lean or is there a sensitivy adj on the governor as on our Power Drawer series?
> --
> John Lebetski
> Chicago, IL
> 77 Eleganza II
> Source America First
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

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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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