Generator Flush

[GibbysWorld]

I am at the 2 year point of ownership of our 2022 37K and with the annual mx for the chassis, the generator is needing a coolant flush. I’ve done this on a car before but not a generator.

What is required/process for the flush and how much coolant is needed? I watched a DP owner flush theirs on YouTube, but they had a slide out for the generator and it seems a little more difficult with the positioning of the Super C.

Thanks in advance.

[Jeepin Jason]

The manual states every 1,000 hours or two years. I only have 100 hours on mine after two years and checked the coolant last month. It looks fine and I am not sure why the recommendation of every two years. Coolant does break down over time, but generally, that is considered to be 5 years in automotive engines. Will be curious to see what others have to say. I am not changing mine on my 2022 this year as it is once again spending the winter at NIRV as they continue to work on warranty issues.

[GibbysWorld]

Nobody has done this?

[Rustynuts]

I haven’t, probably should based on time…..but I have checked with a hydrometer and checked with coolant test strips and it still shows good, so should I? I watched a couple videos on it and it’s pretty straight forward, just tighter than than on a class a but nothing looks difficult.

[Jump in say hey]

As Rusty Nuts mentioned, do the dip stick tests. On our heavy equipment, in addition to using extended life antifreeze, and antifreeze intended for diesel fleet service, use distilled water. We also use an antifreeze additive that John Deere and Caterpillar sell that provided additional protection from cavitation ( hard use and high cylinder wall temps where the boiling oxidative bubbles start). Haven't seen these products sold thru automotive stores. Flushes are subjective to use and your preference. You will find these Onan generators can be hard to belch after draining the antifreeze and then refilling.

[Jeepin Jason]

I guess I should have been more clear on my reply as well. When I said I checked the coolant, I checked it with coolant test strips I purchased off of Amazon. I keep them in the garage for my other vehicles and to test any used vehicle I buy. I have had them show that coolant is bad in the past... On my 2 year old Generator, the results were still well into the correct color band.

[mjc29]

what generator do you have? I have a onan 8k in mine and just did mine a couple months ago. The drain is right on the bottom simple to reach. after that I filled with water and ran until warm, did this 2x. I removed the side cover and then you can pull the overflow tank to make it easier to refill. mine holds 1 gallon. Also makes it easier to change and refill the oil and fuel filter this way. After I filled it up almost all the way I used a small funnel with a piece of clear tubing to finish the job. It took me multiple day since I wasn't in any hurry because when it warmed up to flush I just waited until the next day for it to cool off. I hope this help you.