Cummins Onan Quiet Series Gasoline RV Generator - 4.0 kW, CARB and EPA Compliant, Model Number 4.0KY-FA/6747

Generator was installed and has been running fantastic! Talked to the company that shipped it and they were amazing! We received it long before it was due. The delivery company was awesome as well. Definitely would recommend this company and product.

The Onan 4000 EVAP generator came with our Forester, Sandstorm toyhauler. The first trip out the generator quit, loose wire. A couple years later the air filter bracket fell out, cost $200 to get the fixed, plus 100 mile round trip to Cummins. Then, with only 276 hours on the generator it quit and would not start. Took it back to Cummins to find out a valve came loose, cracked the head, damaged the piston, which destroyed the engine. They recommended just buy a new Onan 4000 Evap and have installed: $4200. Well, ain't going to happen. I will purchase a 4000 watt portable generator to replace Onan. Would not recommend an Onan generator! Nothing but trouble and expenses!

I have this generator on my 2015 Leprechaun Coachman. I got RV new and this unit has been nothing but problems from day one. I did all the maintenance and adjustments on time. It did not matter is was nothing but problems. I lost count of how many times I had to take it back to be fixed and fight with warrenty company to get repairs done. Many of the times I just went ahead and paid for it myself. I have put no less than 2 thousand dollars on a plethora of fixes for this unit. I feel like I have replaced just about every part on the thing. It works for a a few weeks and down again right when you are on a trip. I am so over it! The unit is down right now and I refuse to fix it again. I am buying a portable unit but i should not have too. I basically have a unit onboard that is useless on 150k RV. Don’t do it! Learn from my pain along with others. Onan is garbage and it’s a money Pitt!

The Onan 4000 is a workhorse, probably 1 of the most popular gensets for new rv's. Maintenance is critical on these units. Really just oil changes and valve adjustments, but ignoring either will end your generator by dropping a valve ( the valve retainers wear through if valves get loose). They also have no oil filter, so not changing the oil frequently will also end these generators. They are fairly rugged and fairly noisy. Unless I'm using the A/C on our trailer I just run our small, quiet inverter generator and let the Onan rest quietly. A very, very old design which is due for some upgrades.

Onan is a financial disaster waiting to happen. Look elsewhere and save yourselves thousands of dollars in repairs!