ORIGINAL: DarZeelon
I see a potential problem here...
In a normal (Saito, OS, clones and TT) four-stroke engines, if you hook the crankcase excess oil nipple to the intake manifold:
At low throttle setting the manifold vacuum is high and the blow-by is minuscule...
A long period at low throttle could potentially lead to bottom-end oil starvation, as most of the oil is sucked out from the crankcase.
At high throttle settings this problem disappears, as blow-by increases and manifold vacuum decreases.
If you hook the crankcase excess oil nipple to the muffler, at high throttle settings the pressure in the muffler should be higher than in the crankcase. The result could be 'lubrication' of the bearings with hot exhaust gas...
If we just leave it, your model will just be a bit dirty, after a day of flying...
Isn't this a pretty normal situation, with our 20% oil mix fuel???
Just stop being spoiled brats and wipe your model with Windex™ at the end of the day.
Is it so much of a bother to even raise this issue?
If you can't stand the oil, glow engines are probably not for you...
Dar, is the above an observation? The OS Surpass 70 and larger have been using a PCV system connected to the manifold for a few years now. Has anyone had any issues? I'm sure OS did their homework. It must work well enough that after a few years they integrated the PCV into the the engine design and the user doesn't even have to think about it. The newest engines (FS-200, FSa-56) vent gases and oil past the cam followers into the rocker well and into the intake port via a small hole in the head. The user isn't even involved anymore.
Don't use a window cleaner containing ammonia as it will etch the plastic covering and take the luster right out of it.
What's wrong with asking for cleaner engines?