I checked the serial number a couple years ago and believe it is a '48. Belonged to my father-in-law and he used it around the property. Before he passed he had told me that the pony motor needed re-timed, and possibly the clutch between the pony and main motor was going bad.  It's been sitting for more than 6 years now and despite my intentions of getting it going myself, time and finances are killing that dream.  Wife wants me to scrap it but I want to see it saved or at least be used to save other classics. Would need to get more than scrap value for it. Let me know if interested. Located in Bandon, Oregon.  Will try to get the serial number posted within a couple days 

Is it an ag crawler or a dozer? Wide gauge or narrow? Grant.

It's a dozer. Narrow I believe.. didn't get a chance to reconfirm what I remember today, will go get the serial number tomorrow.

Update.. serial number on this is 3J5831SP.
I has an electric starter creatively mounted so that you can drape a belt over the pony motor pully and not have to use a pull rope to start it. It also has hydraulics to raise and lower the blade that looks like possibly added later in it's life(I am unsure of when and how cat did hydraulics back then). I have the operator roll cage but it isn't on the cat at this time.

a picture helps sale things faster

3J is a narrow gauge tractor, by your serial number it looks like its mid year 1941

Thank you. I appreciate the info. I have been dealing with too many wildfires lately to give this the research I would normally have done.