mark36ph

Hi. I have just got a new nitro engine after being stuck to electric for so long and I am a bit baffled!
Its a TT 75 4stroke I have, and instead of having to fuel nipples, there are 3.
1 in the carb (clunk from fuel tank), 1 on the exhaust (other one from fuel tank) and there is 1 on the back of the crank case which I am not sure whats meant to attach to that.
Anyone any clues for me?
Thanks

tim750r

Its a breather nipple for the crankcase. Run a short length of fuel tube from it to somewhere outside the model. A small amount of oil will come out of this tube when the engine's running.

Good luck :-)

mark36ph

Ahh ok thanks.
Could I attach a T pipe from this to the exhaust and have it come out there? Or is it best just to have a separate pipe to the outside of the model?

Thanks

tim750r

Some 4 strokes feed this back into the inlet manifold (negative pressure) which will help to pull the lubricant through the crankcase as well as expel it neatly (?) but if the TT doesn't have this, a separate pipe is the way to go. I wouldn't try feeding it into the exhaust via the pressure nipple.

Sport_Pilot

Don't put the breather tube on the exhaust as it will pull in exhaust gas when the piston is on the upstroke. This would cause corrosion problems in the crankcase and may not run well.