In Reply to: 9N Oil Canister posted by Bob Ward on May 16, 2020 at 06:28:47:
I'm no expert, but most vehicles of these years had only by-pass filters and they are not particularly effective. At the time detergent oils were not in general use and if you really wanted a clean engine you changed the oil often, generally a thousand miles or less was standard for cars and trucks. I kind of think the filters might have just been a marketing gimmick anyway. If you ever pulled apart an old Ford flathead during the 60's or later it was sure to be filled with sludge so I really doubt the effectiveness of the filters.
I don't worry about changing my filters on my 9 and 8N's, just the oil. Stays pretty clean if done regularly, but I don't put much time on them anyway.
Just my 2 cents!