Splash lube Onans

Not high, just ~450 Onan 4000

I’ve got about 250 hours on an Onan 4000. Have done oil analysis multiple times with good results each time. Have used various Mobil 1 types:
10W-40 High Mileage - sheared down by 40 hours
0W-40 started to shear down at 60 hours
Now running 5W-40 turbo diesel truck

Not sure what you are asking? My generator is a 5500 RVQG and has an oil filters system!

dodge guy wrote:
Not sure what you are asking? My generator is a 5500 RVQG and has an oil filters system!

I’m asking about the longevity of the QG units that are not pressure lubricated and do not have an oil filter.

I blew up the top end of a 4kw Onan at 940 hours. Spun a rocker off the stud, bent the pushrod and likely a valve too when it all went kaplooey. The replacement is at about 300, in 18 months. I change the oil every 100 hours which works out to about 2x a year, typically using Rotella 15w-40.

A friend of mine has a summer place on an island in the Great Lakes.

It is powered by a combination of deep cycle batteries and an Onan 4KY salvaged from a Class C m/h.

Last I spoke to him it was still going strong with MANY thousands of hours on it. It runs during peak demand hours and both powers the demands at hand and recharges the lead acid battery bank.

It also runs ONLY between Easter and (Canadian) Thanksgiving (2nd Monday in October) each year with no monthly ‘exercise’ in between and has flawlessly for several decades.

Several mobile mechanics and utility contractors around here have them on service trucks, they run them well over 10k hours.