There was a Technical Service Bulletin that was in effect for the 1979 and 1980's regarding high oil consumption that required replacing the piston rings and honing the cylinders. Part way though the 1979 model year there was a change to the deep sump pan as noted in the 2 different part #'s depending on engine serial number.
As an interesting note- In my teenage years back when we cooked meals on a campfire, I had a 1965 Honda C95 Dream 150cc bike. Instead of an oil filter it had an oil centrifuge mounted on the right side of the crankshaft. By spinning the crankshaft with the centrifuge on it, the oil was cleaned by the heavier particles being thrown out to the circumference of the centrifuge and getting trapped there. When doing an oil change, you were required to remove the right side cover and pop the cap off of the centrifuge and clean it out. It would be full of black carbon. Worked like a charm and no replacement filters required. As long as the centrifuge had room left in the reservoir for the particles, the oil remained a nice brown color instead of darkening up with carbon black.
I also had an aftermarket centrifuge mounted in my Ford F350 turbo diesel. It used engine oil pressure to spin the internals of the centrifuge at 8000 - 10000 rpm and all the heavy particles would get trapped in the housing which you would clean out when doing an oil change. Very interesting technology from the past and yet we moved forward ?? by going to spin on filters which we change out and toss in the waste?? The price of convenience. Shameful !!
In order to filter out soot particles, you have to run a bypass filter system with a 1 - 2 micron filter. A bypass system takes off a small amount of system pressure oil and forces it through the bypass filter removing all the heavy crap. It also works quite well. I had that set up on a different F350 and I would go 5000 miles between oil changes and the oil was still brown and for a turbodiesel that's amazing.
