Difference between HG42 and OC-3

[Jeff]

Hi all,

I was just wondering what the difference is between a HG42 and an OC-3?

How do u tell the difference between the two??  In what years were these produced?

Also in what year were Cletrac E-31 crawlers  produced?

Thankyou for the help.

Jeff

[John Schwiebert]

This gets alittle tough. An OC-3 is 90% the same as an HG plus some of the improvements made on the OC-3  were then available for the HG model. Look at your crawler and look on the left side of the engine block. There will be a flat area there. The model and serial number of the engine will be stamped there. Behind the mag a date will be cast in the block as to when the block was cast. Start there. On the E I will need to look. Oh the HG was introduced in 1939 and production ended early in 1951.

[Jeff]

Thanks for the info. i have a HG 42 and two possible OC-3's i just picked up.  Ill post some more info when they arrive.

cheers