GMCforum
For enthusiast of the Classic GMC Motorhome built from 1973 to 1978. A web-based mirror of the GMCnet mailing list.
Home » Public Forums » GMCnet » [GMCnet] Onan board Question
[GMCnet] Onan board Question [message #74839] Tue, 23 February 2010 18:29 Go to next message
John Wright is currently offline  John Wright   United States
Messages: 118
Registered: September 2008
Karma: 0
Senior Member
A comment was made a while back on running the Onan without the control
board. What wiring changes are required to do this modification.

--
J.R. Wright
On Location at Florida Space Coast
_______________________________________________
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 board Question [message #74840 is a reply to message #74839] Tue, 23 February 2010 18:43 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
J.R.,

Give Jim B a call as he does this all the time, in fact one of his recent
entries in his Daily Pose mentioned it.

Regards,
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 John Wright
Sent: Wednesday, 24 February 2010 11:29 AM
To: gmclist@temp.gmcnet.org
Subject: [GMCnet] Onan board Question

A comment was made a while back on running the Onan without the control
board. What wiring changes are required to do this modification.

--
J.R. Wright
On Location at Florida Space Coast
_______________________________________________
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

Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426

Report message to a moderator

Re: [GMCnet] Onan board Question [message #74855 is a reply to message #74839] Wed, 24 February 2010 01:03 Go to previous messageGo to next message
mini577 is currently offline  mini577   United States
Messages: 16
Registered: March 2008
Location: Berryville, AR
Karma: 0
Junior Member
I recently did mine as well. Jim sent me an email explaining what he did to make it work. I sort of followed it. Smile

What I did was remove the board and basically all the wires back there. I found a "hot" wire coming from underneath the generator(near the starter) to the board that I used to power the coil/fuel pump. All I did was add a relay back there that connected that hot to the coil. The relay I then triggered with two of the wires coming from the old onan remote panel with a new switch. So - I turn on that switch and get power and fuel..

Next I took one of the other wires from the remote group and added a momentary contact switch with that one wire attached to the switch and the other attached to ground. The generator end of the wire went back to the starter. The starter already has a hot.

I turn on the first switch for a few seconds and get the fuel flowing, and then hit the momentary switch for a few seconds until it starts up. I just have to go back and add a light for the power switch on the panel and add back in the hour meter just for fun.

I don't know if that makes sense to you or not? Smile The majority of the fooling around was trying to figure out the wires going to the remote panel. One of them was bad even after removing all of the plugs and soldering and shrink wrapping the wires together. Luckily I only needed three of them. I like the idea of the brainless onan. It's simple. And if you are watching it like you should you don't need all that extra complication.


Drew

Report message to a moderator

Re: [GMCnet] Onan board Question [message #74867 is a reply to message #74855] Wed, 24 February 2010 07:03 Go to previous messageGo to next message
GMCWiperMan is currently offline  GMCWiperMan   United States
Messages: 1248
Registered: December 2007
Karma: 1
Senior Member
The control board's two most important functions are 1. Prevent attempting
to start an already-running engine. 2. Shut the engine down when the oil
pressure drops.

Function 1 is probably not needed; not even Roger Black, or Ken B., or I
will fail to hear a running 0nan.

Function 2 can easily be included in the relay control -- and should be,
IMHO.

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


On Wed, Feb 24, 2010 at 2:03 AM, Drew Wood <drew@usa650.com> wrote:

>
>
> I recently did mine as well. Jim sent me an email explaining what he did to
> make it work. I sort of followed it. :)
>
> What I did was remove the board and basically all the wires back there. I
> found a "hot" wire coming from underneath the generator(near the starter) to
> the board that I used to power the coil/fuel pump. All I did was add a relay
> back there that connected that hot to the coil. The relay I then triggered
> with two of the wires coming from the old onan remote panel with a new
> switch. So - I turn on that switch and get power and fuel..
>
> Next I took one of the other wires from the remote group and added a
> momentary contact switch with that one wire attached to the switch and the
> other attached to ground. The generator end of the wire went back to the
> starter. The starter already has a hot.
>
> I turn on the first switch for a few seconds and get the fuel flowing, and
> then hit the momentary switch for a few seconds until it starts up. I just
> have to go back and add a light for the power switch on the panel and add
> back in the hour meter just for fun.
>
> I don't know if that makes sense to you or not? :) The majority of the
> fooling around was trying to figure out the wires going to the remote panel.
> One of them was bad even after removing all of the plugs and soldering and
> shrink wrapping the wires together. Luckily I only needed three of them. I
> like the idea of the brainless onan. It's simple. And if you are watching it
> like you should you don't need all that extra complication.
>
_______________________________________________
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 board Question [message #74872 is a reply to message #74839] Wed, 24 February 2010 08:07 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   Canada
Messages: 2277
Registered: June 2008
Location: S. Ontario, Canada
Karma: 3
Senior Member
I agree with Ken, the oil pressure function is very important!

The Onan board is dead simple and the board traces are so big you can solder it with a solder gun!

Resistors should be fine, but the capacitors are likely dried out and the relays should be replaced. Somewhere I remember seeing the DigiKey part numbers for the relays but I can't put my finger on it this morning.

Unless the board itself is destroyed, I'd vote to rebuild it.

JMHO

Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that

Report message to a moderator

Re: [GMCnet] Onan board Question [message #74890 is a reply to message #74872] Wed, 24 February 2010 12:03 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
Messages: 3005
Registered: August 2004
Location: Spanish Fort, AL
Karma: 9
Senior Member
You can always wire a low oil pressure switch so that a drop in oil pressure shorts out the power to the ignition, killing the engine so that low oil pressure does not destroy it first. P.O. on my coach wired this feature into the 455 on my coach, and I see no reason to change it.

Tom Phipps

2012 Phoenix Cruiser model 2552 KA4CSG

Report message to a moderator

Re: [GMCnet] Onan board Question [message #74896 is a reply to message #74890] Wed, 24 February 2010 13:33 Go to previous messageGo to next message
ljdavick is currently offline  ljdavick   United States
Messages: 3548
Registered: March 2007
Location: Fremont, CA
Karma: -3
Senior Member
So do you have to crank up oil pressure before the engine fires up?

Larry Davick
The Mystery Machine

----- Original Message -----
From: "Thomas Phipps" <tph1pp5@yahoo.com>
To: gmclist@temp.gmcnet.org
Sent: Wednesday, February 24, 2010 10:03:26 AM GMT -08:00 US/Canada Pacific
Subject: Re: [GMCnet] Onan board Question



You can always wire a low oil pressure switch so that a drop in oil pressure shorts out the power to the ignition, killing the engine so that low oil pressure does not destroy it first. P.O. on my coach wired this feature into the 455 on my coach, and I see no reason to change it.

Tom Phipps
_______________________________________________
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

Larry Davick
A Mystery Machine
1976(ish) Palm Beach
Fremont, Ca
Howell EFI + EBL + Electronic Dizzy

Report message to a moderator

Re: [GMCnet] Onan board Question [message #74898 is a reply to message #74896] Wed, 24 February 2010 13:44 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
Karma: 13
Senior Member
About one turn of the crank will do it. It's such a Shirley time you
won't notice it.




Emery Stora

On Feb 24, 2010, at 1:33 PM, Larry Davick <ljdavick@comcast.net> wrote:

> So do you have to crank up oil pressure before the engine fires up?
>
> Larry Davick
> The Mystery Machine
>
> ----- Original Message -----
> From: "Thomas Phipps" <tph1pp5@yahoo.com>
> To: gmclist@temp.gmcnet.org
> Sent: Wednesday, February 24, 2010 10:03:26 AM GMT -08:00 US/Canada
> Pacific
> Subject: Re: [GMCnet] Onan board Question
>
>
>
> You can always wire a low oil pressure switch so that a drop in oil
> pressure shorts out the power to the ignition, killing the engine so
> that low oil pressure does not destroy it first. P.O. on my coach
> wired this feature into the 455 on my coach, and I see no reason to
> change it.
>
> Tom Phipps
> _______________________________________________
> 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
_______________________________________________
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 board Question [message #74913 is a reply to message #74898] Wed, 24 February 2010 16:48 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
Karma: 13
Senior Member
That was supposed to be "short" time.

Don't you love these automatic
spell checkers that change what you type?


Emery Stora

On Feb 24, 2010, at 1:44 PM, Emery Stora <emerystora@mac.com> wrote:

> About one turn of the crank will do it. It's such a Shirley time you
> won't notice it.
>
>
>
>
> Emery Stora
>
> On Feb 24, 2010, at 1:33 PM, Larry Davick <ljdavick@comcast.net>
> wrote:
>
>> So do you have to crank up oil pressure before the engine fires up?
>>
>> Larry Davick
>> The Mystery Machine
>>
>> ----- Original Message -----
>> From: "Thomas Phipps" <tph1pp5@yahoo.com>
>> To: gmclist@temp.gmcnet.org
>> Sent: Wednesday, February 24, 2010 10:03:26 AM GMT -08:00 US/Canada
>> Pacific
>> Subject: Re: [GMCnet] Onan board Question
>>
>>
>>
>> You can always wire a low oil pressure switch so that a drop in oil
>> pressure shorts out the power to the ignition, killing the engine so
>> that low oil pressure does not destroy it first. P.O. on my coach
>> wired this feature into the 455 on my coach, and I see no reason to
>> change it.
>>
>> Tom Phipps
>> _______________________________________________
>> 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
> _______________________________________________
> 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

Report message to a moderator

Re: [GMCnet] Onan board Question [message #74914 is a reply to message #74913] Wed, 24 February 2010 16:51 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Emery,

Yes, especially when they provide a bit of humor to start the day! ;-)

Regards,
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 Emery Stora
Sent: Thursday, 25 February 2010 9:48 AM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] Onan board Question

That was supposed to be "short" time.

Don't you love these automatic
spell checkers that change what you type?

Emery Stora

On Feb 24, 2010, at 1:44 PM, Emery Stora <emerystora@mac.com> wrote:

> About one turn of the crank will do it. It's such a Shirley time you
> won't notice it.

> Emery Stora

_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426

Report message to a moderator

Re: [GMCnet] Onan board Question [message #74915 is a reply to message #74913] Wed, 24 February 2010 17:02 Go to previous messageGo to next message
Dennis S is currently offline  Dennis S   United States
Messages: 3046
Registered: November 2005
Karma: 2
Senior Member

Emery,
I thought perhaps "Shirley" was some Aussie term that Rob taught you.

Dennis


Dennis Sexton
73 GMC
Germantown, TN
USA



-----Original Message-----
From: Emery Stora <emerystora@mac.com>
To: gmclist@temp.gmcnet.org <gmclist@temp.gmcnet.org>
Sent: Wed, Feb 24, 2010 4:48 pm
Subject: Re: [GMCnet] Onan board Question


That was supposed to be "short" time.
Don't you love these automatic
pell checkers that change what you type?

mery Stora
On Feb 24, 2010, at 1:44 PM, Emery Stora <emerystora@mac.com> wrote:
> About one turn of the crank will do it. It's such a Shirley time you
won't notice it.




Emery Stora

On Feb 24, 2010, at 1:33 PM, Larry Davick <ljdavick@comcast.net>
wrote:

> So do you have to crank up oil pressure before the engine fires up?
>
> Larry Davick
> The Mystery Machine
>
> ----- Original Message -----
> From: "Thomas Phipps" <tph1pp5@yahoo.com>
> To: gmclist@temp.gmcnet.org
> Sent: Wednesday, February 24, 2010 10:03:26 AM GMT -08:00 US/Canada
> Pacific
> Subject: Re: [GMCnet] Onan board Question
>
>
>
> You can always wire a low oil pressure switch so that a drop in oil
> pressure shorts out the power to the ignition, killing the engine so
> that low oil pressure does not destroy it first. P.O. on my coach
> wired this feature into the 455 on my coach, and I see no reason to
> change it.
>
> Tom Phipps
> _______________________________________________
> 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
_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
______________________________________________
MCnet mailing list
ist Information and Subscription Options:
ttp://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

Dennis S
73 Painted Desert 230
Memphis TN Metro

Report message to a moderator

Re: [GMCnet] Onan board Question [message #74917 is a reply to message #74915] Wed, 24 February 2010 17:24 Go to previous messageGo to next message
k2gkk is currently offline  k2gkk   United States
Messages: 4452
Registered: November 2009
Karma: -8
Senior Member

I just figured it was some sort of "Mac" weirdness!

Mac Macdonald
Oklahoma City

(:-;)


> To: gmclist@temp.gmcnet.org
> Date: Wed, 24 Feb 2010 18:02:48 -0500
> From: dennisfsexton@aol.com
> Subject: Re: [GMCnet] Onan board Question
>
>
> Emery,
> I thought perhaps "Shirley" was some Aussie term that Rob taught you.
>
> Dennis
>
>
> Dennis Sexton
> 73 GMC
> Germantown, TN
> USA
>
>
>
> -----Original Message-----
> From: Emery Stora <emerystora@mac.com>
> To: gmclist@temp.gmcnet.org <gmclist@temp.gmcnet.org>
> Sent: Wed, Feb 24, 2010 4:48 pm
> Subject: Re: [GMCnet] Onan board Question
>
>
> That was supposed to be "short" time.
> Don't you love these automatic
> spell checkers that change what you type?
>
> Emery Stora
> On Feb 24, 2010, at 1:44 PM, Emery Stora <emerystora@mac.com> wrote:
>
>> About one turn of the crank will do it. It's such a Shirley time you
>> won't notice it.
>
>
>
>
> Emery Stora
>
> On Feb 24, 2010, at 1:33 PM, Larry Davick <ljdavick@comcast.net>
> wrote:
>
>> So do you have to crank up oil pressure before the engine fires up?
>>
>> Larry Davick
>> The Mystery Machine
>>
>> ----- Original Message -----
>> From: "Thomas Phipps" <tph1pp5@yahoo.com>
>> To: gmclist@temp.gmcnet.org
>> Sent: Wednesday, February 24, 2010 10:03:26 AM GMT -08:00 US/Canada
>> Pacific
>> Subject: Re: [GMCnet] Onan board Question
>>
>>
>>
>> You can always wire a low oil pressure switch so that a drop in oil
>> pressure shorts out the power to the ignition, killing the engine so
>> that low oil pressure does not destroy it first. P.O. on my coach
>> wired this feature into the 455 on my coach, and I see no reason to
>> change it.
>>
>> Tom Phipps
_______________________________________________
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 board Question [message #74920 is a reply to message #74915] Wed, 24 February 2010 17:35 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Dennis,

Close! The Aussie slang for a girl/woman is "Shelia" mildly derogatory.

Here's a few more that relate to the fair gender:

Dog: unattractive woman
Mappa Tassie: map of Tasmania - a woman's pubic area
White pointers: topless (female) sunbathers

Regards,
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 dennisfsexton@aol.com
Sent: Thursday, 25 February 2010 10:03 AM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] Onan board Question


Emery,
I thought perhaps "Shirley" was some Aussie term that Rob taught you.

Dennis


Dennis Sexton
73 GMC
Germantown, TN
USA



_______________________________________________
GMCnet mailing list
List Information and Subscription Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426

Report message to a moderator

Re: [GMCnet] Onan board Question [message #74952 is a reply to message #74867] Thu, 25 February 2010 04:30 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
Senior Member
GMCWiperMan wrote on Wed, 24 February 2010 07:03

The control board's two most important functions are 1. Prevent attempting
to start an already-running engine. 2. Shut the engine down when the oil
pressure drops.

Function 1 is probably not needed; not even Roger Black, or Ken B., or I
will fail to hear a running 0nan.

Function 2 can easily be included in the relay control -- and should be,
IMHO.

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




You do not need to hear it. You can feel it. A simple red light across the output could also be added to show it is running. The light could be part of the switch. I agree that the low oil pressure shut down would be easy to implement.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

Report message to a moderator

Re: [GMCnet] Onan board Question [message #74955 is a reply to message #74915] Thu, 25 February 2010 06:14 Go to previous message
Steven Ferguson is currently offline  Steven Ferguson   United States
Messages: 3447
Registered: May 2006
Karma: 0
Senior Member
Dennis,
That would be "Sheila", heh heh.

On Wed, Feb 24, 2010 at 4:02 PM, <dennisfsexton@aol.com> wrote:

I thought perhaps "Shirley" was some Aussie term that Rob taught you.

--
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

Report message to a moderator

Previous Topic: [GMCnet] GMC in TV Commercial
Next Topic: [GMCnet] Tire rotation sequence & frequency
Goto Forum:
  


Current Time: Sat Sep 21 09:17:06 CDT 2024

Total time taken to generate the page: 0.01117 seconds
.:: Contact :: Home ::.

Powered by: FUDforum 3.1.1.
Copyright ©2001-2021 FUDforum Bulletin Board Software