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Topic: Wiring Diagram For 12 Volt part of Onan 7.KW in '91 U280/300 (Read 920 times) previous topic - next topic

Wiring Diagram For 12 Volt part of Onan 7.KW in '91 U280/300

Hi folks, anyone got the circuit diagram for the 12 volt side on the Onan 7.5Kw diesel generator on a '91 U280/300?  I have a '91 GV U280 factory equipped with the Kubota powered Onan 7.5Kw generator normally found on U300s of that era.  My manuals include the 120 VAC part, but nothing about the 12 volt side of things on the generator.  I am trouble shooting a starting problem I apparently caused when I installed the battery monitor on the coach batteries.  I removed the jumper that tied the negatives on the coach and engine batteries together, since the shunt had to go between the  negative and the ground on the coach batteries only.  Apparently this impacted the starter circuit for the generator.  I suspect the ground from the generator will have to be modified, but not having a diagram I am not sure how it is currently connected.  Any suggestions?

 
Mike & Lilli
1991 GV U280 36' SBI, 3208 Cat, Build #3825
4320 Watts Solar
Kansas City, MO

Re: Wiring Diagram For 12 Volt part of Onan 7.KW in '91 U280/300

Reply #1 –
My Onan has a part number for the wiring diagrams on the nameplate. Hope this helps.
Old Phart Phred, EIEIO
89 GV ored 36' #3405 300 hp cat 3208 ATAAC side radiator, mountain tamer exhaust brake

Re: Wiring Diagram For 12 Volt part of Onan 7.KW in '91 U280/300

Reply #3 –
I guess I could have been clearer.  Is there even supposed to be a diagram of the 12 volt portion of the generator wiring that Foretravel created on the coach, not the Onan made part on the generator itself?  Something that shows the preheat and start switches on the dash and in the bedroom?  Also any high current leads to the coach battery for starting?  With much of the wiring I am never sure if I am missing a page or it simply never existed.
Mike & Lilli
1991 GV U280 36' SBI, 3208 Cat, Build #3825
4320 Watts Solar
Kansas City, MO
 

Re: Wiring Diagram For 12 Volt part of Onan 7.KW in '91 U280/300

Reply #4 –
The diagram link I posted shows it.12vokt battert feeding the starr start circuit on generator. The wires are connected to on if your b.v batteries. It shows that in the diagram.  Which one  I do not know. There is no diagram that foretravel did as far as I know. I went through my 91 schematic and it does not show anyyhing.. you are probably going to have to trace the bundle to the battery. I'd start at the starter battery terminal on gen and work back from there. You must have disconnected a battery hot or ground.
91 GV U300 Unihome 40' Build 3811
6V92TA Detroit