I'm learning now the reasons I dearly wish I had gone for a used 721d instead of the gas engine ZTR I bought instead. Lots of issues (dropped valve at 460 hours, fouling carb & plugs, very sensative to fuel & ethonol content.) Not that the Kubota Gas engine would be near so troublesome---not at all. But the additional torque of the diesel and the fact that since it's designed to run at full load, full speed everyday all day would make me go for the diesel. Plus better resale value. You do NOT need 29 hp on that unit to power through tough grass.
You need to consider gallons of fuel per hour used.
The diesel will probalby use considerably less than my 18-hp gas unit.
The gas 29 hp unit will use considerably more than either unit (and really, you don't need that much power).
That said...if you need a weed mower, look for a small used tractor and attach a 3-pt mounted Woods mower to it. It's hard to tell by your description it's intended use, but don't fool around using a $12k finishing mower as a brush & weed mower.
You need to consider gallons of fuel per hour used.
The diesel will probalby use considerably less than my 18-hp gas unit.
The gas 29 hp unit will use considerably more than either unit (and really, you don't need that much power).
That said...if you need a weed mower, look for a small used tractor and attach a 3-pt mounted Woods mower to it. It's hard to tell by your description it's intended use, but don't fool around using a $12k finishing mower as a brush & weed mower.