I burn approximately 1 gallon per hour of diesel.
approx $1000.00 every 200 hours for a full service.
grease every 10 hours
Safe to assume $10/hr just for consumables
You also need to consider the capital cost of the machine over its useful lifespan (10,000-20,000 hours?), the cost of money tied up in the asset for it's lifespan,...
If you need numbers call around to see what the machine rents for. Rental companies generally only hang onto equipment as long as they are generating income and not becoming money pits in terms of repairs and maintenance.