Generator charge/power wire......

[JackE]

So back on this again.... Onan Genset III 6500 watt gas powered, 2 circuit

I got my generator hooked up the rest of the way. Start/stop from the dash switch works great. The original fuel pump was leaking so I replaced it with a 12V pump. Before I hooked it up to the original power wire that comes from the generator, I had the thought to check voltage on that wire. With the generator running, it is producing 114 DC volts. I have checked this multiple times on different settings on my DVOM. I switched to AC setting and it reads something like 56V. With the positive lead hooked to that power wire, I did get a shock when I touched the negative lead. I'm confused about the readings I'm getting. The only thing I haven't checked is to see if the old pump will run on 12V. Currently I have the new pump running off a switch on the dash powered by the bus 12V system. The start battery for the generator is an isolated circuit to the generator only. The generator is not grounded to the chassis. On the original motor home, the generator was grounded to the chassis, and starter power was tied into the house battery system. Anyone have ideas on what I'm seeing?

[Native]

Is this the unit?


A-1389 Onan Commercial Emerald-6500 Genset spec sheet (2000).pdf


Even if it is not, the contact information for Cummins/Onan are at the bottom.

[JackE]

Originally Posted by Native

Is this the unit?


Attachment 46159


Even if it is not, the contact information for Cummins/Onan are at the bottom.

It's not the same unit, but darn close. Thanks for finding that. I'll contact someone who can get me the right manual, and hopefully the right spec sheet to figure this thing out. This one you found is for the 95-01 model, mine came out of a 88, so not that new.

[BlackJohn]

Jack E


I have the same model Onan as you likely in my old motor home, an 85.


Start power for it is off the rv start batteries.

The fuel pump is fed right from the control box and 12v dc, not remotely switched as yours is.
Grounding is thru the chassis in the way it is all mounted, no visible ground wire.
I don't think the fuel pump should be fed anything other than 12v dc and can't understand your voltage readings at all.


I can't get to it at the moment as I am having back troubles and can barely walk. Will look it over when able.


John

[JackE]

Originally Posted by BlackJohn

Jack E


I have the same model Onan as you likely in my old motor home, an 85.


Start power for it is off the rv start batteries.

The fuel pump is fed right from the control box and 12v dc, not remotely switched as yours is.
Grounding is thru the chassis in the way it is all mounted, no visible ground wire.
I don't think the fuel pump should be fed anything other than 12v dc and can't understand your voltage readings at all.


I can't get to it at the moment as I am having back troubles and can barely walk. Will look it over when able.


John

The original application in the motor home, the pump was powered right from the generator like yours is. It's now powered from a separate switch because I set it up that way so I can run the carb dry when it's going to be sitting for a while. I also added a dedicated battery for the generator, mostly because I had one sitting around not being used, but also because I didn't want to run a big cable back to the bus batteries. However, without a charging source for that battery, I'll likely just run the power cable to the bus batteries and ground through the chassis one of these days.

Sorry to hear about your back issues, that's definitely No Bueno!! My back isn't what stops me, but I have neck problems that can put me right out of commission, it's definitely no fun. Get feeling better, I'm in no hurry for the right answer, lots of building to do before we hit the road.

[Native]

I can relate to the back problems, John. Please take care of it and take it easy for a while. If anyone gives you gruff about it, tell them I said so!

[BlackJohn]

Jack, I do like the separate switch for your fuel pump with today's crappy gasolines. These were built to run on hi octane and before unleaded, methanol etc.
Thanks to you and Native for well wishes re my back. Spinal cord bulging out of lower discs. They can't fix it at my age and only one med can touch the pain issue. At 80 bucks a pop every 4 hours, too rich for my blood. And the withdrawls are something else if one tries to get off of them.
My advice to all, don't get old before you finish your bus.


John

[Native]

Aw man ... I got old before we bought our bus!