I'd say not if well maintained - it wouldn't put me off if the price was right and all else ok. But then I run a petrol Range Rover V8 4.6 with 209,000 miles on the clock!
Remarkably - people do neglect service . A boat has just now gone up for sale at the brokerage at our marina and the advert proudly says its engines were last serviced in November 2014 !!!!! And its asking £149k .
I must be bonkers as I service my engines annually. I also keep a file with receipts .
Surveyor I used on latest purchase said the 300 odd hours on it amounted to just about run in, looked after they run for 1000s & he has commercial clients that testify the fact. (He is also a VP trained engineer & expert witness)
Check for good service history and that correct oils etc used, if non genuine bits have been used that’s a good indication that it’s been done on the cheap, it’s worth paying someone who knows what they are doing to have a good look, will save you in the long term.
I’m on a commercial boat at the moment fitted with D6s and they’re currently showing 6451 a side if that helps. She gets used 12 hours a day every day.
If it were a diesel engine in a car or van, you would go about 12,000 miles between services and expect to get at least ten years out of it. If you reckon on an average road speed of 40mph, then 12,000 miles works out at about 300 hours. Therefore ten years lifetime equates to something like 3000 hours.
- marine engines run at very high % power when compared to a road engine. A car does not need much power to keep it at speed once it is moving.
- car engine don’t rot as they are used more frequently
I am not saying 900 ish hours is an issue ( it isn’t ) but the comparison to a road engine is not really valid as the loads and use pattern are so different