Re: 1966 Kiekhaefer 500 Fuel Economy?
General rule of thumb for 2-cyle outboard where HP was rated at the crankshaft (such as your old Merc) and not the prop, is HP/10=consumption at WOT (Wide-Open Throttle).<br /><br />I.E., your 50 HP Merc will use approx 5 gallons per hour of 50:1 premixed fuel at full throttle.<br /><br />Some motors, due to design inefficiencies, will use more. The old 50HP and 75HP V4's were a good example of this. I had an old 75 Ev that used at least 9 gallons per hour. Couldn't afford to run it nowadays!<br /><br />Although your 50 is old, it's a very good design, and quite economical if in a good state of tune. Be sure the motor is propped correctly, if you run too large of a propeller and the motor can't spin up to its recommended rpm range, it'll use much more fuel.<br /><br />HTH........ed
