F: Onan Genset…

Update: Apr. 2022

I came here to Tucson accidentally back in November 2021 as I’d intended to go to Amado and hang out for a couple weeks before crossing the border at Nogales on the way to Mazatlan. But when I arrived at Amado, I found that the RV park I always stay at was sold and being remodeled so they had no where for me to stay. So I headed back to Tucson (an hours drive north) and stayed at the Pina County Fairgrounds. Kinda way out there in the east of town but the only economical RV park I could find while in a hurry to leave Amado. I had scouted around Amado but there weren’t any parks with economical spaces available, and they were all pretty much filled with snow birds. And than one of my readers of this blog happened to notice I was in Tucson, invited me over for a beer and when I got there, I found he had a 2 RV parking area. With water and sewer, but no 50 amp electric for the 2nd RV. I asked if he’d be interested in letting me camp there, he said sure if I helped him install a 50 amp outlet. Yes! So we installed a 50 amp receptacle. And so I moved in here on Dec. 6th, 2021. Saving money too as the monthly is less then most RV parks in the region.

And shortly after I’d moved in, I heard the generator start up on it’s own. WHAAAA? Yep, it started up by itself. So I checked the tooth pick I have jammed under the outside start switch and it’s fine…

If I press on the switch with that toothpick there, it’s impossible start the engine. But John has mentioned that there are packrats here in the area so maybe one chewed the wiring somewhere under the RV? And caused a short? Kinda a long shot when you think about it. Didn’t do anything specific about it at that time.

Hmm. ‘Tis a mystery. Well, okay, I’ll keep my eye on it. And then, speaking of eyes, I woke up one morning in February with a torn retina so I’m still here in late April because of the operations and follow ups.

And the morning of April 22nd, I happened to notice that the generator was running. And it had 10 hours on it since the last time it was run (yes, I keep track)! Since it was noon when I found it, that means it started up at 4 AM. Again, checked and the toothpick is fine. Inside the RV, I could press the ‘Stop’ switch to shut it off, and then disconnected a couple wires going to the hallway switch that Starts/Stops the generator, as a test.

It’s started by itself now twice.

I looked all around in that mess of covered bundles of wires there under the hood and couldn’t find any evidence of a rat chewing on plastic. No debris on the ground, nothing under the RV hood that I could see, nothing odd in that bundle of wires.

And again today, after 5 days of it behaving, I noticed it was running again. It started ~two hours before I got up and I caught the fact it was running just a few minutes after.

Grr. So then I decided to look for some way to disconnect the control wiring so it won’t start up again without my actively starting it. Took a while to finally find the multi-wire connector, felt kinda dumb that I’d had to refer to the drawings in the book (something I should have done earlier) to find how easy it was to trace the cable from the left side of the generator down the cable to the connector right in front of the generator case. Easy to find when doing it that way. So I disconnected that multi-wire ‘remote’ control wiring and so far it’s been fine but it’s not been more than a few days. If it doesn’t start for weeks, that will sort of point to there being a problem with the Start/Stop/meter wiring. I have already looked carefully at the wiring to both switches involved, one on the dash, and one on the hallway’s Power Control Center and it all looks good, but at this point, I don’t know…most anything could be wrong.

What if it starts by itself again? The fact that the remote cable is now disconnected will tell me that whatever it causing it is inside the case. But if I’m not in a place to work on it, then I’ll have to climb under the RV and disconnect one of the main battery cables so it can’t start on its own. This is a heavy piece of equipment so it’s not something I can just lift out and work on it, so I’m hoping I find something simple.

May 2018 – Visit to Winnebago Factory for service

I had scheduled work on the RV at the Winnie factory in Forest City, Iowa and while I was there had arranged for the standard maintenance on the Genset. This is an Onan Quiet Diesel 7500 unit and when I bought the RV the genset only had 185 hours on it. Not being run enough. This one isn’t on a slide out so it was hard to tell much about it but it didn’t look bad, the oil seemed OK, it didn’t overheat when I ran it a couple hours so I put off doing a formal maintenance procedure for 2 years while I racked up hours on it every month. Always ran well. I was told it had been serviced by the consignment dealer I bought it from but that’s not likely to be true, considering all the other things they didn’t do. But, here I was two years later at the Winnie factory so, why not have it done here.

What the tech told me and showed me after was that he’d found a mouse nest inside the air filter case. The air filter was chewed up, but not too badly, so he didn’t think any paper ended up inside the engine. Whew. He showed me the chunks of dog food the mouse had dragged in there so it looked like it was building a home. At some random time after it began I started the genset engine and s/he got out of there quickly. Most likely fell on the freeway because that’s where I usually run the monthly 2 hours.

The service tech did an Onan factory service type thing. It got a new air filter, fuel filter, oil filter, then the AF was tested OK, and the output voltage tested OK. So I’m good for another 10 years I hope. These Onan gensets are designed for 10,000 hours of use as a backup emergency generator and I’ve only got 235 hours on it now so I’m hoping that it will give me many years of service.

Shortly after purchase of the RV – Nothing to report on the Genset yet. 

One of the things I noticed at the dealer’s lot was that the Onan Genset only had 176 hours on it. They ran it for me for an hour and it did fine. The runtime hours are a little low for it’s age. I should get off my duff and change the oil and filter because I know the freakin’ dealer wouldn’t have done that. The unit still only has 185 hours on it even after I ran the genset for 7.1 hours April 1, 2016. Ran the AC the entire time I was parked in a stores parking lot. Who knew it gets hot in the Phoenix area!

The engine sounds nice. These Onan’s are built for 10,000 hours before needing a major overhaul but they tend to be underused in a RV. They are supposed to be run under load for a few hours per month, not just per year. This one has been run, on average, 13 hours per YEAR. That’s 1.1 hours per month. And that includes the 7.1 hours I just put on it. Based on Onan’s recommendation of 2 hours per month minimum with 1/2 load, this one has only seen half as much runtime as recommended. I’ll rectify that over the next few months.

Edit – Sept. 2016

So I’m sitting at my computer desk perusing FaceBook inside the RV and notice a sound…hmmm. What is that? So I get up and walk to the front of the RV and discover that the genset is running? Huh? I don’t think I have a autostart circuit for my genset. Looking at the Winnebago spec sheet, NO, I do not. OK, I have a mysterious genset startup.

So I go outside and check out the top of my genset and everything looks normal. I do need to run it this month so I let it run while I try to figure out how it started itself. And I sit down to ruminate on the problem. After 30 minutes or so of ‘thinking’, I head back to the computer. Sitting there, I glance out the window, and there’s the neighbors CAT! Hah! There’s the culprit! Over the previous 2 weeks or so, I’d noticed that cat walking under my RV several times.

Knowing the cause, I tried to think of a simple solution to the random cat, rodent, snake, or raccoon that might climb up to the top of the genset and step on the start switch. Had all sorts of ideas over the next hour. Went outside and checked the start switch and wondered if I could make it harder to press-to-start. But then, realized, HEY, I can just jamb the switch with a toothpick. So, yep, that’s what I’ve done. A toothpick prevents any critters from stepping on the start switch and starting my genset inappropriately.

Turned out this has happened to many RVers and some of the solutions are expensive, some are ridiculous, and most are humorous. None are as simple as a toothpick. So if your genset starts up mysteriously on occasion, just jamb a toothpick under the outside start switch.

 

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