After reading about the screen vs filters this is what I take from it all. The reason the screens were issued originally is that back when these engines were first designed the most common oil used was a straight-mineral oil. The oil was cheap and thus not as big an issue with frequent oil changes. Heck, I still think oil is cheap insurance for our engines. The screen kept larger particles from damaging an engine, but smaller particles continued to circulate until the engine was shut down. Then they dropped to the bottom of the sump and settled out. Dispersant oil was invented to keep the small stuff suspended so as to drain out with the oil, the idea being to extend engine life and reduce crud remaining in the engines and subject to being dislodged and sent through the system. That is when filter elements came into popular use in order to filter out particles re-circulating with the dispersant type oil. If using AD type oil then an oil filter is necessary to keep those suspended particles from recirculating.
Run up/ Leak test
Panorama of the shop
With the new parts installed, the aeroshell oil added and the top cowling installed it was time to get home. Roger added the notation in the Adlog for the work, I paid the bill and we saddled up. I taxied out to runway 31 and departed to the north. I gave some thought about lunch at KMQS, Chester county but diverted back to Wilmington. We flew through a light shower but the clouds were not looking good. I decided it was best to get on the ground and find a place to eat rather then get stuck away from home if thunder boomers moved in. A fun day flying even though it was only .9 in the log. As always great to have Vince along and what would I do without his photo skills!