Owan circuit board Issue?

Bob Dunahugh

New member
Sep 17, 2012
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Put both tanks in that had no gas. Put 5 gals in. That took care of my short test drive. Don't think that there's enough gas to have the Onan gas pickup tube in the gas supply. So I filled the carb float bowl. By using a squeeze bottle to the gas line to the carb. The 4000 watt Owan started up right away. But stopped when I removed my finger from the start switch. Ran a jumper wire from the battery. To the coil. Runs, and puts out 110 Volts. I know my way around the Onan engine. But the circuit board. That's another story. The circuit board is $150. But it appears to me. That is what I need. RIGHT? Bob Dunahugh
 
Jump terminal 5 to 9. If it runs then, yes, you probably need work on the
board.

bdub

> Put both tanks in that had no gas. Put 5 gals in. That took care of my
> short test drive. Don't think that there's enough gas to have the Onan gas
> pickup tube in the gas supply. So I filled the carb float bowl. By using a
> squeeze bottle to the gas line to the carb. The 4000 watt Owan started up
> right away. But stopped when I removed my finger from the start switch.
> Ran a jumper wire from the battery. To the coil. Runs, and puts out 110
> Volts. I know my way around the Onan engine. But the circuit board. That's
> another story. The circuit board is $150. But it appears to me. That is
> what I need. RIGHT? Bob Dunahugh
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Bob,

I had a friend that recently had the same problem. He replaced the control board and it still would not keep running. He discovered on his Onan it was the oil pressure switch.

Gary Bovee
Red Bluff, CA
1978 GMC Royale
www.gmcidiotsguide.com
 
Bob,

I had a friend that recently had the same problem. He replaced the control board and it still would not keep running. He discovered on his Onan it was the oil pressure switch.

Gary Bovee
Red Bluff, CA
1978 GMC Royale
www.gmcidiotsguide.com
 
Bob, this indicates K2 ain't staying in. Check the easy stuff first. 5Amp fuse on the circuit board. Oil pressure switch (Simply remove the wire
from the switch to test). Bad contacts on K2 - burnish them and try again. Bad K2 - measure the coil resistance on the circuit board. If it's very
high, the relay coil is open. Report back what you find.

--johnny
--
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" - ol Andy, paraphrased
 
9 to 5 also includes the fuse on the control board in rlyhe circuit. So if it doesn’t run be sure to check the fuse

Emery Stora
77 Kingsley
Frederick CO

>
> Jump terminal 5 to 9. If it runs then, yes, you probably need work on the
> board.
>
> bdub
>

>>
>> Put both tanks in that had no gas. Put 5 gals in. That took care of my
>> short test drive. Don't think that there's enough gas to have the Onan gas
>> pickup tube in the gas supply. So I filled the carb float bowl. By using a
>> squeeze bottle to the gas line to the carb. The 4000 watt Owan started up
>> right away. But stopped when I removed my finger from the start switch.
>> Ran a jumper wire from the battery. To the coil. Runs, and puts out 110
>> Volts. I know my way around the Onan engine. But the circuit board. That's
>> another story. The circuit board is $150. But it appears to me. That is
>> what I need. RIGHT? Bob Dunahugh
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
> Bob, this indicates K2 ain't staying in. Check the easy stuff first. 5Amp fuse on the circuit board. Oil pressure switch (Simply remove the wire from the switch to test). Bad contacts on K2 - burnish them and try again. Bad K2 - measure the coil resistance on the circuit board. If it's very high, the relay coil is open. Report back what you find.


In case it wasn’t mentioned previously - the AC voltage from the flywheel alternator must be present at terminal 8 on the board in order for the K2 relay to latch and thus permit the engine to keep running after the start button is released.

Jumper battery+ to coil+ so that you can keep the engine running and then measure the flywheel alternator voltage between terminals 8 and 11. It should be somewhere around 28V with the engine running at governed speed.

—Jim

Jim Miller
1977 Eleganza
1977 Royale
Hamilton, OH