ORIGINAL: fastplane
Gray beard, thanks for the note. I never use after run oil in my four strokes. I only run fuel out when at the field. After arriving home I pour Marvel Air Tool oil into the case by using the case vent hole. I rotate the crankshaft severl times to distribute the oil into the bearings.
So, I am quite disappointed in the deposits on the bearings after several flights. I am thinking the Marvel oil is leaving deposits. That is why I am looking for a really good 'white' oil the will not discolor and or leave deposits while setting in the garage. One thing nobody has mentioned is how do they tune the Saito 4 strokes. If you peak out the RPM while tied up , how much do you back off RPM to get acceptable amount of oil to the engine bearings when in the air? Considering the prop unloading at higher speed.
Same as any other engine, get it to the max RPM then back off the needle until the RPMs drop 3 to 500. Where we live I tend to fatten them up about 500 +or- a few. I fly the plane then decide if it should be adjusted a little more. Once I get them set I don't fiddle with the needles unless I change prop size or when the weather starts to change. Right now my engines are tuned for 100+ degrees but as winter sets in they will slowly get fattened up a click at a time. I average about 4 clicks fatter in the winter. People forget how cold it gets in the desert but the engines know all about it. Seeing tourists come here in shorts at Xmas time then swearing about how cold it is is always funny.
