Community Forums

Devarona · 06-16-2018, 01:40 PM

I'm at Mike Thompson in CA, trying to buy a 2017 Minnie Winnie 22R. It was a previous rental. Everything is in ideal conditions except for the Genny. These guys are saying they'll fix it but I have to sign papers for them to service it first. I drew the line there and left the lot.

I tried two others of the same RVs and one works great but the other has the same issue of lagging or shutting off when the AC is turned on.

Anyone know of these have had issues with the fuel pump or hoses before? They're all Onan 4000s btw.

powercat_ras · 06-16-2018, 05:24 PM

The Onan 4000 has a small dial on the carb behind the access door that is used to set the altitude. Settable from 0 to about 7,000 feet. If that dial is set way off it can cause issues. I have never had issues with fuel pump or fuel hoses on any of the RVs with Onan 4000s I have owned over the years.

Onan 4000s still have a carb and it is not serviceable, if Generator is allowed to sit and never used, then the carb may be fouled and might need to be replaced. Be sure to run your Onan 4000 generator for at least 1/2 hour a month to prevent this from happening. I start it, run it no load 5 minutes, run it under load using AC for 20 minutes, shut of the AC and let run another 5 minutes, then shut it off.

My Vista's Onan 4000 is a bit finicky. I often have to hold down the engine start button for 20 seconds or longer before it "catches" and start. It is also very important to just touch and release the stop button when shutting it off. If you hold down the stop button it activates a prime function that can flood the engine making it more difficult to start the next time.

My Onan 4000 will also lag if I forget to turn off the AC and all loads hit the Onan at once when it connects power to the RV after the transfer switch delay. It works best for me if I wait and turn on the AC a minute or so after the Onan connects power to the RV.

Devarona · 06-16-2018, 10:25 PM

Man... I've got a 2914 Thor Four Winds that has a 4000 and I haven't had one issue with it, 800 hours later... I'm thinking the hoses don't come well sealed on these and dust gets all over...

luvlabs · 06-17-2018, 09:15 AM

Good for you for resisting the hard sale tactics. Tell the dealer that you are prepared to buy the unit once they can demonstrate that all systems are working. You would be happy to purchase after the PDI and their correction of any problems uncovered. They want to sell, they will be back.

MSHappyCampers · 06-17-2018, 10:51 AM

Hi !

Welcome to IRV2! We're sure glad you joined the gang!

I'm not familiar with that genny.

Good luck, happy trails, and God bless!

Mich F · 06-17-2018, 04:37 PM

I bought my current MH when it was new. The Onan 4KY generator would not start. I was told after they got it running that it was a bad fuel pump. I did hear of a couple of other new units, around the same time, that had the same issue.
More recently I had a surging issue. Sometimes a little, other times really bad. I was getting a code of engine unable to maintain required frequency. I turned the altitude adjustment and it smoothed right out. That was OK for a while but the surging returned. I called a mobile Generator repair guy a couple of months ago, to look at it. The first (and only) thing he did was to loosen the screw that holds the altitude adjustment lever, and then play with the adjustment quickly. moving it up and down, then it smoothed right out again, and its been fine since. He did say if you are not careful doing that you can screw something up. I forget what though.