ORIGINAL: WRM
I have a Saito FA 72, it keeps eating the rear bearings up .
This is the third set of bearings . It eats the bearing cage up inthe rear bearing. One was the factory bearing, one was put inby Horizon Hobby, and I have just put the third one in myself thatI got from Boca Bearing. The factory bearing and the Horizon hobby bearings all had metal shields on them. The Boca bearing does nothaveshields. I think it is the shields that don’t let them oil properly. I haven't tested the new bearings. As soon as I test the new bearings I will let you know what happens. The old bearings lasted about one gal. of fuel. The fuel thatI run is Wildcat 30% nitro with 18% synthetic oil-no castor. Horizon calls for 20% oil.Wildcat says their 18% is a heavier viscosity and does a better job than thelighter 20% oil.
Does your FA-72 have the plastic rear crankcase cover? If so, perhaps vibration of the cover is rubbing against the rear bearings during operation? If this is the case, I would consider replacing the plastic rear crankcase cover with the aluminum one. I did this with my FA-72.
-Mike