05-05-2022, 09:26 PM
Hi Tony
Very true. I dunno about the "classic" oils but I suspect these not too classic. In the early 1950s API SC was about the maximum. Dunno what cheap supermarket oils are now but way past API SC. From the mid 50s engine wear on cars new and old decreased markedly. Wear was mostly corrosion related. Presumably whatever protects the cyls also protects the roller mains which were a source of trouble on Sevens (My father used to recount how pre war Len Southward, later of motor museum fame, told him Sevens came in to his workshop with the flywheels rubbing on the crankcase!)
In the last 20 years cyl wear on moderns has almost ceased. Cylinders retain hone marks at mileages which to the early 50s qualified for a rebore.
Very true. I dunno about the "classic" oils but I suspect these not too classic. In the early 1950s API SC was about the maximum. Dunno what cheap supermarket oils are now but way past API SC. From the mid 50s engine wear on cars new and old decreased markedly. Wear was mostly corrosion related. Presumably whatever protects the cyls also protects the roller mains which were a source of trouble on Sevens (My father used to recount how pre war Len Southward, later of motor museum fame, told him Sevens came in to his workshop with the flywheels rubbing on the crankcase!)
In the last 20 years cyl wear on moderns has almost ceased. Cylinders retain hone marks at mileages which to the early 50s qualified for a rebore.