Air cooled generator. 20w-50?

[Chris142]

My wife bought a toyhauler a few weeks ago. The generator is an air cooled Onan 4k. The previous owner was using 10w30 in it.

The paper air filter is pretty oily due to vapors from the crankcase vent being plummed to the air box. Maybe worn rings? Oil hot and thin? Combination of both maybe.

Ran it tonight them changed it's oil. It holds 1.6 qts. No oil filter.

Had just enough maxima 20w-50 to use in it.

Onan recommends 15w40. Supposed to be 108F this weekend and she will be wanting to run the ac unit on top of it.

 

[ripcord]

It will be fine with 20w50. Any low noack oil from 0w40 to 20w50 will give good service.

 

[ripcord]

Heck, if it was an oil burner, I probably just use SAE 40w.

 

[Chris142]

Heck, if it was an oil burner, I probably just use SAE 40w.

I have some of that too

 

[Mainia]

I would run some Redline 10w 40 and call it a day.

 

[Kamele0N]

Heck, if it was an oil burner, I probably just use SAE 40w.

In MB 229.5....NOACK 10 or less...

 

[Zaedock]

I have some of that too

Stolen from your tractor.

 

[greywolf]

My wife bought a toyhauler a few weeks ago. The generator is an air cooled Onan 4k. The previous owner was using 10w30 in it.

The paper air filter is pretty oily due to vapors from the crankcase vent being plummed to the air box. Maybe worn rings? Oil hot and thin? Combination of both maybe.

Ran it tonight them changed it's oil. It holds 1.6 qts. No oil filter.

Had just enough maxima 20w-50 to use in it.

Onan recommends 15w40. Supposed to be 108F this weekend and she will be wanting to run the ac unit on top of it.

With the paper filter being oily, by chance had the crankcase been overfilled with oil??

Let us know how the thicker oil works out, I'm having the same problem with my Onan 4KW air cooled, since day 1.
Thanks.

 

[Chris142]

With the paper filter being oily, by chance had the crankcase been overfilled with oil??

Let us know how the thicker oil works out, I'm having the same problem with my Onan 4KW air cooled, since day 1.
Thanks.

Possible I guess. I plan on rerouting the crank case vent away from the air filter.

 

[cronk]

I run Amsoil 15w40 Signature series Diesel oil in the Onan P218 on my John Deere 318.
These engines seem to like a thicker oil, in your hot climate, I think the 20w50 will be excellent.

 

[greywolf]

Possible I guess. I plan on rerouting the crank case vent away from the air filter.

Great idea, this past weekend I disconnected the crankcase vent from the filter housing, connected another hose and routed it out the oil filter drain hole. Ran it for a few hours, all good.

 

[greywolf]

Great idea, this past weekend I disconnected the crankcase vent from the filter housing, connected another hose and routed it out the oil filter drain hole. Ran it for a few hours, all good.

OIL DRAIN PLUG PROTECTION PLATE, not oil filter drain hole.

 

[Chris142]

Great idea, this past weekend I disconnected the crankcase vent from the filter housing, connected another hose and routed it out the oil filter drain hole. Ran it for a few hours, all good.

I did the exact same thing! I even put a small breather on the end of the hose.