View Single Post
Old 11-04-2017, 07:03 AM   #55
ranger58sb
Guru
 
ranger58sb's Avatar
 
City: Annapolis
Vessel Model: 58' Sedan Bridge
Join Date: Aug 2013
Posts: 6,570
Quote:
Originally Posted by Nomad Willy View Post
But in defense of the trucks they climb 80 times as many “hills” as the boat engine. Just say’in the comparison is a bit weak.

Chris going down the hills IMO isn’t applicable to this issue.

My point was only that the comparison isn't all that great. 65 MPH downhill, no load... not much like typical marine constant propulsion situation.

On the idea of continuous ratings mentioned in a few posts... Our 3-cylinder Yanmar genset motor runs at 1800 RPMs and is probably rated to do that all day every day forever. The (almost) same motor in our home tractor runs at way more RPMs (no tach, but I'd guess 3000+) when implements are in motion, and the rating probably takes into account that nobody runs a tractor like that for more than 8-10 hours/day max. (A guess.) I'd also guess that engine would maybe rev even higher if ungoverned.

-Chris
__________________
Chesapeake Bay, USA
ranger58sb is online now   Reply With Quote