Cruise speed with Volvo MD6A diesel
I have recently purchased a Dufour 31 with MD6A 10HP diesel. In the next month I need to decide whether to remove and repair the motor or replace it with a Yanmar 18hp. The repair will be a small portion of replacement expense, but don't want to throw good good money at a bad or underpowered motor. So my first question is to ask anybody with an MD6A and similar sized boat if they feel they have enough "horses under the hood" to cruise at a decent speed under power. Second, if properly repaired / rebuilt, will I get a few good years out of the MD6A or is it likely to give me problems?