Anybody have experience with really old Diesels?

Old Merc diesels are great engines,they were also used as an industrial engine,very durable,built to last forever but not for h.p. I think the same as dartwagon just leave it alone,probably couldn't get much more out of it anyhow.I had the experiance of working on 4 and 2 cylinder mercedes motors in some old TK reefer units. If diesels sit for a long time and compression is low due to dry rings daredevils idea of wd-40 works great, provides sealing and lube for rings and is combustable to help starting, ether can ignite from glow plugs and break rings from the explosion.