It says on the box, that the belts aren't for automotive or lawn equipment use. I'm puzzled by that. If the TD-14 is like the WD-9, that fan belt is quite wide. Top pulley can be squeezed together and I imagine that even an A-belt would run there. Bottom pulley -- not so. Wrong width belt would tend to bottom in the groove. Not good for any belt to run bottomed. A power-twist would be especially ugly.

Of course, a guy running an IHC crawler instead of a pretty yeller one ain't gonna be too concerned about ugly.