How to prevent exhaust residue making a mess!
 

I have a secondhand 50 size ARF Mustang, powered with a side-mounted O.S.50 2-stroke, fitted with an in-cowl Pitts-style muffler.
The 2 metal exhaust tubes are fitted with standard silicon extensions to exit the cowl beneath the plane.
Fuel mix is 10% Nitro, 15% synthetic oil, 85% methanol.
The plane flies exceedingly well.

BUT - after every flight there is a large amount of oily residue right along the bottom of the fuselage!
I have tried cutting the end of the silicon extensions on an angle hoping that would help suck the residue away from the plane, but that didn't help. Maybe the angle was wrong?

Please, does anybody have an exhaust setup solution or an engine tuning solution to reduce the oily mess in these circumstances?

I have checked all fuel connections, engine and muffler bolts, etc and that all seems to be ship-shape.

Thanks,
Bill

RE: How to prevent exhaust residue making a mess!
 

That's the nature of 2-strokes. Longer extensions may help, but not much.

Sounds like you may want to look into a 4-stroke ;)

RE: How to prevent exhaust residue making a mess!
 

As said - this is the nature of glow engines.

If you REALLY don't want to deal with the slime of caster oil when you fly, you only have two options;

Fly Electric,
OR
Go big with a Gas engine.

RE: How to prevent exhaust residue making a mess!
 

Or get a 4-stroke

Saito's tend to put out more slime than the others, but aside from them, 4-strokes put out so little that I rarely even bother to clean my planes after flying.

RE: How to prevent exhaust residue making a mess!
 

But,
The YS 1.20 burning 20/20 fuel (20% nitro and 20% oil) is very messy. They like to run rich.  I have one in my P-40. The oil means the engine is getting lubricated well, and it's a great engine!

Dash

RE: How to prevent exhaust residue making a mess!
 

A 15cc or 20cc gas engine should fly the plane well and leave no oily mess at all. You may be able to sell the OS .50 and buy a Chinese gas engine for little additional cost. Good luck.

Sincerely, Richard