In Reply to: Re: Oil flow mystery posted by COLVIN on October 09, 2020 at 21:06:46:
There's nothing mysterious about these vintage parts and machines. I referenced my May, 1949 MPC to answer the drain plug item, p/n 358042-S. Forget page numbers, means nothing as it depends on which MPC you are looking at. So, it appears based on the May, 1950 MPC that the drain plug was obsoleted, most likely in April, 1950 when many major changes were made. "...It seems they just expected us to live with a cup of the old dirty oil in every new batch (or siphon/rag.)..." No. No drain plug, so why don't you loosen the oil line on the bottom at the brass inlet, p/n 9N-18679 and drain oil from there? Flush with Mineral Spirits (charcoal lighter fluid or paint thinner, same stuff), wipe with shop towels/rags, then reinsert line. Maybe I should have stated above in my method that you should relive some pressure by removing the canister lid bolt and loosen or remove lid when draining oil pan. I have an early 8N and don't bother with my drain plug anymore or muck with the line. Once filter is removed, I wipe out old remnants with rags, pour some spirits in and wipe up excess. Repeat as often as you wish. For your gauge issue, as I suggested, blow out line at gauge point, if that doesn't work, try a new gauge, if that doesn't work time to rebuild oil pump. since that requires dropping the pan, you are half way to an engine rebuild tear down so...your call. I have a few slightly used oil Pressure Gauges; I could send you one, you pay $10 to include postage. It's not rocket science. C'mon! We're talking about an oil change -how basic can you get? Some thing just require using common sense. SEE LINK from our HOW-TO's for more info.