I find it odd there is no breather on the carburetor. What keeps dirt and bugs from getting pulled into the engine? Do they make breathers? If so, do they affect the way it runs because of restricted airflow? Or...am I missing the boat completely, is it SUPPOSED to have a breather and I didnt' know about it?

Thanks,

Wings

Dirt wont hurt the engine?

Dirt will hurt the engine. RC cars that use glow typically will have a oil wetted sponge breather or filter. Typically, air is "clean" once you break ground. It is only the ground handling one needs to be worried about. If you fly from grass or pavement, your probably alright. Once in the air there isn't much dirt up there. If your field is very dusty... well... I guess your engine will eat some dirt. Don't worry about it... it is probably OK as long as it isn't really dusty.

You could fashion a air cleaner of sorts I suppose, but they tend to rob a lot of power. It will vary from engine to engine I'm sure. I tested one of my engines both ways. W/O air filter, I was getting 9300 RPM. With the cleaner I was getting 9000 RPM. This may not seem like a lot at first, but prop RPM is exponential as it relates to power. I was losing 0.4HP (3.6HP vs 3.2HP estimated) just from the air cleaner. Thats over 10%!

A small piece of pantyhose held in place with an O rings seems to keep most of the larger crap out. Cheap, easy to change .

Ditto on what Norm says... get out the pantyhose :bananahea

Since we fly off a dirt runway I would never take an engine to the field without an air cleaner. A crash off field can put a lot of junk into the carb barrel. It will hurt the engine by scratching the polished internal surfaces such as the crank throws and bearings as well as the cylinder. Common practice at our club is never turn an engine by hand after a crash. Take it home and clean it. Tower sells Bruline carb air filters in a couple of sizes. I never thought of the pantyhose approach but it sounds good to me.

I fly off grass, and no one around here bothers with air cleaners much. But we don't have any blowing dirt or sand around either.

But in a crash, the carb can get filled with dirt, the "don't ever turn it after a crash" advice is always good no matter where you fly.

How do you clean it? Sorry, I'm new. I need to know these things.