I'm not sure as there's no hour meter owner before me said he had about 250-300 hours so I'd make a rough estimate a and say 600-700. Both lower units I had serviced (seals, pumps etc). Both oil tank pumps and resovoirs replaced. Carbs removed and cleaned, new plugs, new starters in both. All preventative maint my friend is a mechanic and we went over engines with a fine toothed comb to see what could eventually give us a problem and took car of it. I'm sure there's more ill check my receipts and let you know if I forgot something