The International Cessna^® 170 Association

Many folks change oil and filters at 25 and 35 hour intervals. I've always changed oil at 50 hour intervals. Of course that assumes fairly frequent flying. In my opinion oil should be changed at least every 6 months, or 50 hours. Same with the filter.
In Jamaica my planes didn't have filters- only oil screens and we changed oil at 50 hour intervals, which was about every 2-3 weeks. Always went to TBO, no problems. That was with Cont. O-470's, IO-520's, IO-360's and Lyc O and IO-540's. Always used Aeroshell W-100 except for break-in.
I know oil is cheap and now I only fly about 120 hours a year, but I'm lazy and why waste the stuff ?
Rudy

FWIW, I have a spin-on filter & I change oil & filter every 35 hours. When I had just the screen I went 25 hours on the oil changes.
A local FBO does 50 hour oil changes on their rentals & they seem to always go to TBO.

Eric

I've had a recommendation to run multigrade A.D. oil from the get go, The recommendation is do a minimal run-up then take=off a run the snot out of it.

c170b53 wrote:I've had a recommendation to run multigrade A.D. oil from the get go, The recommendation is do a minimal run-up then take=off a run the snot out of it.

My engine overhauler recommended that I break my engine in using Phillips XC20-50. I did so,since that's what I like to run anyway. Broke in just fine. With around 550 hours SMOH,I just went about 22 hours after an oil change before I used a whole quart. Not too bad!

Eric