New oc-3 owner

[flying crawler]

Hello everyone.  I just bought a oc-3 an hauled it home this weekend.  I needs undercarriage work but the price was right.  I have a bit of a mystery thought.  I engine that is in this crawler is overhead valve.  This had me kind of puzzled since I know it shoud be a flat head.  It doesn't lok like it's cobbled into the crawler.  All the mounts line up with the originals.  It has the goveenor, distributor, and oil filter on the right side of the engine and the carb, exhaust, and generator on the left.  Also the starter sticks out the back of the engine on the right side.  I don't know it it's possible a transplant from a later model of oliver tractor?  Any thoughts would be appreciated.  Also a couple of questions...

1. Has anyone installed weld on sprocket rings on their sprockets and if you did where did you get them?

2. Does anyone know of a source for pins and bushing other than Landis, his price wasn't that high but when I called they don't have any right now and I wanted to get moving on the undercarriage work.

Thanks for any help you can give me.

Mike

[John Schwiebert]

First question: Are there any casting numbers on this engine block? Is this a four cylinder engine. Are there any model or brand identifcation numbers on the distributor or starter. What kind of carburetor is on the engine?