Re: Cummins Merc QSD4.2 diesel sterndrive
Is this a repower? New boat?
There is not a whole lot of diesel experience here. I have a 30 year career in diesel engines, primarily truck, and primarily Caterpillar. I love the newer, lightweight, high speed diesels and I generally believe that all of the products from the major manufacturers are good. I am not one who looks at the high performance nature of these products and suggests that there will be life issues. Depending on the planned application and use, these could live forever with proper maintenance. On the other hand if they were misapplied where they were running at full load 100% of the time, then they would have quite a short life. These ratings (Recreational) are intended for 1 hour out of 12 at full load and cruise more than 400 RPM below rated speed (3900), so less than 3500 RPM Cruise RPM. If that's how these engines are expected to be used (or less) than I think they should be awesome.
