It occurs to me that owners of the original, older M3Ws must find this a humorous thread. If their machines didn't leave oil spots after a run, then something is wrong!
Friend of mine over here in the UK used to have a 1972 Austin 1300, a wonderful British Leyland miracle of engineering, running the 1275cc A-Series engine. It smoked like a bar-steward all the time, but went much better than and 1300 before it, for reasons we never really worked out. We used to tool around as youthful car mates all the time and followed the car regularly - whenever it stopped smoking we knew it was down on oil and let our mate know. All good and entirely sustainable. He then took the car to university, losing his wingmen and seized the engine within weeks....
Like all things Morgan, accept the rattles, clocks, leaks and foibles, and just worry like hell when it starts behaving like normal......
