Re-powering with Single Left Hand or Counter-rotating Engine

Optimizing the performance of Boston Whaler boats
Tom D
Posts: 1
Joined: Sun Dec 12, 2021 8:23 pm

Re-powering with Single Left Hand or Counter-rotating Engine

Postby Tom D » Sun Dec 12, 2021 8:29 pm

What problems can occur in a single engine re-power if a counter-rotating engine is used?

ASIDE: I have a 1983 Newport 18. I have found a model year 2000 low-hour Yamaha 150-HP Ox66 left-hand or counter-rotating engine.

jimh
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Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
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Re: Re-powering with Single Left Hand or Counter-rotating Engine

Postby jimh » Mon Dec 13, 2021 8:10 am

Counter-rotating engines are usually identical to the standard rotation engines except for the gear case. The availability of repair parts for the gear case may be lower for a counter-rotating engine.

The number of propellers available for a counter-rotating engine will be less than a standard rotating engine.

The effect of propeller torque will be in the opposite direction on a counter rotating engine.

The resale value of a counter-rotating engine may be lower than a standard engine.

ASIDE: the Yamaha Ox66 engines are probably the best of the older two-stroke-power-cycle engines due to their closed-loop sensor and control of fuel metering design.