582 Rotary Valve oil

[TY2068]

Has anyone ever heard of using 20W-50 motor oil for 582 Rotary Valve lubrication. When I got my Kitfox I found what appeared to be motor oil in the tank vs. 2-cycle oil as you would expect. I've run across a few obscure posts on different forums where guys advocated using motor oil. Something about 20W-50 containing lots of Zinc thus providing better gear lubrication and anti-foam properties. Upon draining the motor oil out the system I discovered no particles indicating wear or coolant contamination. I figure maybe a few of you guys that have been around Kitfox's for a long time have heard of this practice before ?
I don't have anyone in my area to talk with who knows much of anything about the Kitfox or the 582's. I in-fact had to point out to a new Kolb driver with a 582 that he needed 2-cycle oil in his Rotary Valve tank. He was under the impression that if you pre-mixed then you could skip having oil in the Rotary Valve circuit. Yea, he was flying it like that.. tank empty. Eyes rolling !

[dynomike]

if it was light in color ,similar to honey ,it could have been amsoil intercepter 2 cycle oil.

[tx_swordguy]

Rotax Rick (whom I bought my 582 from) puts straight 30wt in rotary valve and that is what I have been using as well. I would NOT run it dry and expect premix to do the lubricating (I also premix). My understanding is the rotary valve shaft is a seperate and completely sealed unit from the crank case/ pistons etc that gets lubed by the fuel mixture. I doubt it truly matters since it is just supposed to be recirculated anyway.

[TY2068]

It was definitely motor oil as it had a distinct smell vs. 2-cycle oil. I did not know the Rick guy advocated using 30W. I suppose unless you have RV oil either leaking internally into the crankcase or into the cooling circuit (or both) it would do no harm. The only purpose of RV oil is to lubricate the RV bearings, seals, and gear to gear splines anyway. Being that the RV chamber is a "sealed chamber" it does make some sence that motor oil would provide better lubrication properties for this critical area. Any leak in this area would be detected just as with 2-cycle oil (milky RV oil or RV oil consumption).
I have limited experience with 582's so I take some opinions with a grain of salt. One thing however that caught my attention was this. It was said by several who have pushed 582's far beyond normal 300hr TBO that motor oil was the way to go. The prior owner of my plane (A&P) evidently subscribed to that chain of thought. Interesting. Thanks for the info guys.

[LORENZ]

The come new from rotax filled with motor oil.

[TY2068]

Hi Lorenz,

How did you come about knowing this ? Was there some documentation or instructions that came with a new engine that pointed this out ? Was the motor oil to be drained-replaced or just left in there ?

[LORENZ]

Rotax Rick documented it. He now sends all of his motors out with 30w motor in there now. Im opting to keep 30w in there, because as you described, there's gears in there.

1 caviate. If the seals start wearing and the motor starts burning the 30w as noted by having to top off the reservoir bottle, I will change it over to 2 stroke oil. I'd rather burn 2 strike oil at 100% rather than 30w at 100%. I think both would burn just fine in those small amounts that weep into the case past the seals, but still, I'd rather burn 2 stroke oil instead of motor oil given the option. The motor is looking to need a rebuilt at that point anyway, so the gears arent going to be turning in 2 stroke oil for too long.

[TY2068]

Hi Lorenz, forgive me but I'm still not clear on this. Rick documented what exactly ? I assume you are saying that Rotax Austria built and delivered new engines with motor oil in the RV tank rather than 2-cycle oil. Subsequently Rick discovered this and adopted the practice himself. Is that correct ? As far as published engine literature goes this is not a factory advised practice. Not that I'm aware of anyway. If motor oil is the way to go I'd definitely like to be using it. As you mention as long as the engine isn't comsuming oil then what is the disadvantage ? Anyway my engine had mo-oil in there and I want to know the rational behind it. I definitely agree that I'd rather burn leaking 2-cycle oil.

Thanks,
Ty

[TY2068]

A friend of mine showed up at the strip the other day in his just purchased completely refurbished Kolb Mark III. The plane has a brand new (not rebuilt) 582. Well what do you know dark blue 2-cycle oil in the injection tank and what appears to be brown-ish clear motor oil in the Rotary Valve tank. He is new so I got a puzzled look when I pointed that out. Of course he wanted to know why ? My answer...Hell if I know ?