Mercedes diesels were push-startable well into the 1980s. They still had glowplugs (even in the 60s) and if you did have a battery they would heat up the preco

Mercedes diesels were push-startable well into the 1980s. They still had glowplugs (even in the 60s) and if you did have a battery they would heat up the precombustion chamber to lighten the load on the starter motor.