Does anybody on here with some time running 985's have any oil opinions?

Brian

I was only permitted to use Aeroshell W-100 oil for 1200 or so hours on one. Never saw issues, and mechanics were happy.

But, they are just aircraft engines.....run a good quality aviation oil and I doubt you'll go wrong.

MTV

Philips 25-60 is the best I have used in many different round engines.

Kurt

Phillips 25-60 is fine... XC is fine, Aeroshell 15-40 is fine. I worked as a tech-rep on these engines for about 3 years in the 90's. Part of that was that when I wasn't on the road, I filled in wherever I was needed in the shop. Usually that was the cylinder shop or buildup, but I spent lots of time in teardown as well. You could tell when an engine came in that was run with Aeroshell or XC...they were so nice and clean inside! (if it was changed with regularity). It was quite the education! The volume I saw and had "hands on" sure made "trends" easy to see. We had a few operators that were still stuck on mineral and straight weight oils...those engines were so messy!
John

The 985 in my Stearman is approaching 1800 hours. It's had W100 and 25W60, and lately W120 (cause it's leaking so bad). Compressions are still excellent.

Barnstormer wrote:The 985 in my Stearman is approaching 1800 hours. It's had W100 and 25W60, and lately W120 (cause it's leaking so bad). Compressions are still excellent.

Assuming that's total time?

hardtailjohn wrote:Phillips 25-60 is fine... XC is fine, Aeroshell 15-40 is fine. I worked as a tech-rep on these engines for about 3 years in the 90's. Part of that was that when I wasn't on the road, I filled in wherever I was needed in the shop. Usually that was the cylinder shop or buildup, but I spent lots of time in teardown as well. You could tell when an engine came in that was run with Aeroshell or XC...they were so nice and clean inside! (if it was changed with regularity). It was quite the education! The volume I saw and had "hands on" sure made "trends" easy to see. We had a few operators that were still stuck on mineral and straight weight oils...those engines were so messy!
John

The big question would be how much of the parts went back into each engine? I'm guessing that the nasty ones only needed gaskets. While the clean ones need all new moving parts.

clippwagon wrote:

Barnstormer wrote:The 985 in my Stearman is approaching 1800 hours. It's had W100 and 25W60, and lately W120 (cause it's leaking so bad). Compressions are still excellent.

Assuming that's total time?

SMOH.

[/quote]

The big question would be how much of the parts went back into each engine? I'm guessing that the nasty ones only needed gaskets. While the clean ones need all new moving parts.[/quote]


No... one of oil's biggest and most important functions is carrying away debris and grit. The really nasty ones usually had LOTS of wear on the wear parts as the debris and grit were kept recirculating. The clean ones were pretty much standard replacement parts at overhaul. Not always...but generally.
John