The Gun Counter

Rotax calls for 50:1 premix ratio in their 2-stroke watercraft and airplane engines.

Rec Power Engineering claims their Blue Max 100:1 oil should be used at 80:1 ratios(according to the company rep on the phone) in Rotax engines. They claim it is a "highly concentrated oil". LINK
However, I'm leery. Seizing an engine while miles down the Red River(or worse yet, while flying) is A BAD THING.

What say you?

I always believe the engine maker over the (potential) snake oil salesman. But I only have experience with cheapie 2-strokes, not a Rotax.

I wouldn't do it without a specific call out in the engnie's maintenance specifications, or written confirmation from a Rotax engineer on Rotax letterhead. Even then I probably wouldn't do it.

"Highly concentrated oil" sets off all kinds of bulshit alarms.

Catbird wrote:"Highly concentrated oil" sets off all kinds of bulshit alarms.

What does that even MEAN?

What's the worst that could happen if you mixed that "highly concentrated oil" at 50:1? The engine would smoke a little bit? All two strokes smoke a little bit.

I used to run a Jett 0.35 on a mix of denatured wood alcohol and castor oil, but the Rotax is a little bit bigger than that.

What, you didn't know they cut those "low-rent" oils w. water?

Just out of college I sold lubricants. I wouldn't trust the lube guy, I'd trust the engine manf.

What they said about the claims. Further, I would choose a lubricant that makes recommendations that are more in line with the engine manufacturer's instructions.

CByrneIV wrote:Actually, if there was too much oil in the premix, the valves and ignition could both end up unhappy.

That said, I trust Rotax to know their engines... They have some really solid engineers. I do NOT trust the claims of lubricant manufacturers.

This is an oil that Rotax recommends.

As for too much oil in the mix, fouled plugs and carboned pistons with stuck rings can be a result.

The only reason I was considering the other stuff is because at 80:1, it saves some money. And Aircraft Spruce is a little high on their shipping costs.

Termite wrote:The only reason I was considering the other stuff is because at 80:1, it saves some money. And Aircraft Spruce is a little high on their shipping costs.

I think that is pursuing a false economy.