Originally Posted by TWerner
400/250 is 1.6. So if I read that correctly, your 3 diesels are running 60% more hours total, but burning 6% less gallons of fuel than your 3 gas mowers? That comes to almost exactly 41% less fuel burned.
I assumed the diesel and gas mowers were the same size and mow at the same speed. It's more than a 41% savings if the diesels cut more per hour.
Using $3.50/gallon to be conservative, and 50 gallons/week on gasoline, that's $175/week on gasoline versus $105/week on diesel. Buying ag diesel might make the savings a bit more, say $75, but even so, if you only save $25 a week on a mower running 400 hours a year, it will take a while for a diesel to pay for itself.
For a better analysis, I'd need the hours per week per mower.
Then I can plug in the numbers to show how much you save per hour on fuel. Again, I am assuming your diesels and the gas mowers cut the same area per hour.
I tend to agree, the savings on fuel is small. I average 350 hrs each per year on two mowers. Based on a 40% reduction on my fuel consumption, I would save about $400 per year (per mower) on fuel by switching to diesel. So unless a diesel mower is more productive, and saves on labor costs, I don't think I can justify the up front expense of a diesel.
All things being equal (other than the engine), how much more does a diesel upgrade cost on a mower?