I had a long post written, and hit a wrong key and erased it. When I owned a Diesel repair shop and road service in central California back in the late 1970's, I was a distributor for the Frantz oil filter system sized to fit a LuberFiner 750 oil filter canister. The tissue paper filter element for that one was about 8" in diameter and over a foot tall, and the canister held about 2 gallons of oil. The Cummins and Detroit engines it was designed for usually held 10-15 gallons of oil, depending on the engine application. We would change filter elements every 10,000 miles and simply add enough oil to replace the volume lost during a filter change. Some of those engines had over 100K miles on the oil, and laboratory analysis of samples taken during filter changes indicated no loss of lubrication capability or other deterioration of the oil. Saving 8-10 gallons of oil per change was a major advantage of running the very efficient bypass filter. The engines were also equipped with a regular full flow filter, but it was only changed about once a year because there were virtually no large contaminants to filter out. The oil got black, like all diesel engine oils do since the sooty carbon is almost impossible to remove due to its extremely fine particle size, but the filter media kept the oil performing like new under operating conditions a gasoline engine virtually never sees. Good luck on your project!
Jerry
