RE: Oil Test Summary by rc bugman
Amsoil Dominator 50:1 oil mixed at 20:1. Gas was 93 octane.
The engine was run full throttle for 6.5 hrs. During this time period, 3
gallons of fuel was burned. For the first 2.5 hrs, the engine was propped
with a 22 x 10 prop and the head temperatures fluctuated around 180 degrees
F. With this prop, the engine turned 6200 rpm. In an effort to raise engine
temperatures to the 220 degree F range, the prop size was increased to 24 x
10 for the final 4 hrs of the run. Engine rpm were 6000 and head
temperatures fluctuated around 200 degrees F. Outside temperature was 30-32
degrees F.
In 6.5 hrs of running, there was significant carbon formation on the top of
the entire piston and in the entire dome of the cylinder. There was no
carbon formation on the ring or in the ring groves. The carbon had a
brownish cast and was very hard. Carbon layer was in the range of 10-15
thousands thick.