29-11-2019, 04:42 PM
It's worthwhile pointing out John that whilst the M (motor) number on the crankcase can give you an approximate date, don't forget that after 80 odd years there's no guarantee that the rest of the engine is original or contemporary to the crankcase. Many cars (mine included) have engines that have been made up from bits of others as a long time ago there were plenty of spares available quite cheaply in scrap yards and breakers. There are other parts of the engine assembly which carry a serial number, such as the flywheel and the engine block (inside the valve chest) which might indicate their date and which might or might not match the crankcase number!