P&W R985 with Hamilton Prop preferred oil

[CowboyJake]

I fly in MN, ND, and SD spraying in the summer. Been running aeroshell w100 with pretty minimal oil consumption. Switched over to Phillips 25w-60 and it seems to use way more oil. I wanted to switch for safer/easier startups and warmups but anyone have opinions on what’s best?

 

[Mikey52]

The straight aeroshell is what we always used in 985's, 1830's, and r2000's. In the Howard with a R2800 we used a Texaco 50 wt. but the aeroshell was used most often. In radials the thicker oils when cool don't slip by the bottom pistons rings, so hydraulic lock didn't happen as often.

 

[CowboyJake]

Ok that is good to know. I’ll stick with the 50 weight I think.