Mikecam

Putting this in a GP Cub. Stupid question but I thought all 4 strokes had crank case vents? Am I missing something? Also I believe that it is a ringed engine so what fuel should I use. Thanks

w8ye

My Feedback: (16)

The OS 70 Surpass II has closed crankcase ventilation. There is a line connecting the crankcase vent to the intake manifold

Regular two stroke fuel works fine in them.

10% - 15% nitro is fine preferably with some castor oil in the fuel

Cherokee Flyer

Omega 15% runs great in this engine. Have been trying to wear one out for a year or two now.

L.

DHaxton

Hey, I am running this same engine in a U-can-do .46. I am curious as to whether there are any suggestions for prop size. I have been flying with a 14x6 APC but I think I have too much prop for the plane. I am running around 9500 rpm without any overheating. If I decrease the prop size and increase pitch or decrease the prop to a 14x4 will I get more performance Hovering? I don't feel like I am getting enough thrust so maybe you could give me some ideas about what would be the ideal prop as well as rpm range. Top Flight etc..With less prop it seems like I would get more rpm's and therefore more thrust. Is this rational thinking?

w8ye

My Feedback: (16)

APC 14 X 4W

maukaonyx

I use a 13x6 APC on my Excelleron with this engine and it pulls real nice, also using 15% Omega currently. Ran it for a long time on 15% Cool Power and it was the same to me. Like the other guy, I don't purposely look for the 4stroke fuel, and this OS and all my others seem to not care about that at all...they run fine on 2 stroke fuel. My son has the same engine too, in a Yak 54 and he can hover it pretty good on a 14x4, using 15% Cool Power. Hope that helps. Jon

Mikecam

Thanks guys. I run Omega 10% and have a 12x7 apc for it. I'm hoping to have her in the air in 2 weeks.