300, 340, 350 or what?

If this works you'll see a picture of a 330U. the 330 had a 135 cid engine. Hope this helps.

Thanks for the tips but your picture didn't come through however. I tried to give it a shot and have posted a rough picture of the tractor without sheet metal. I am still curious why the larger CID engine on the 300 has less drawbar HP than the 135 CID engine on the 330. The tractor is about 3 hours away so I won't be able to try to identify it until next week.

* * * **PTO HP** **Drawbar HP**
model (max) (rated) (max) (rated)
300U: 41.26, 36.41, 37.36, 29.61
330U: 34.24, 29.95, 31.77, 24.31

The 330U compression ratio is higher (7.38 vs 6.8) so it may be a bit more efficient, but the 300U still has the edge in power.

Afraid I'm not good enough to tell you what's in the picture, but certainly could be a 300U - chances are good it is since about ten times as many of them were built as 330Us. Hope you enjoy whichever it is.

It sounds as though you definitely have one of the utility models since they were the ones with the downward exhaust. The serial number tag on the 300U and 350U was located on the right side, to the rear of the distributor. It may be still there and just painted over.

If you can't find it, the year can be determined by date codes on the major castings. These look something like 06*29*A, which would be June 29, 1955. 1956 is B, etc. The 300U was made from 55-56, the 350 in 56-57, and the 330 and 340 came after that.

Another clue would be engine size. This should be stamped on the right side of the engine. The 300U used the C-169 (cubic inch) engine, the 350U had the C-175, and the later tractors had smaller engines (something like 125-130 cubic inches).

Hope this helps.