MONTAUK 17 Auxiliary 4-HP Engine
Posted: Thu Aug 05, 2021 10:24 pm
by michaux
On my MONTAUK 17 with a Yamaha 90-HP two-stroke-power-cycle engine I have an auxiliary Yamaha 4-HP two-stroke-power-cycle engine. The standard propeller for the 4-HP auxiliary is a 7-1/2 x 7-pitch.
What is the best propeller for the auxiliary engine for trolling and for use in emergency [as a get-home engine]?
--Frank
Re: MONTAUK 17 Auxiliary 4-HP Engine
Posted: Fri Aug 06, 2021 8:49 am
by jimh
With a 4-HP engine as the auxiliary propulsion engine, the MONTAUK 17 will never be able to achieve any boat speed other than a displacement mode speed.
I have no basis to recommend a "best" propeller.
What is the maximum boat speed that the MONTAUK 17 can obtain now with the 4-HP and its "standard" propeller?
Do you have a tachometer on the 4-HP engine?
I would expect that alternative propellers would just vary in pitch by 1-inch. If the auxiliary engine seems to be lugging when running at full-throttle, a reduction in pitch is probably necessary.
Check with Yamaha to see if they offer a High-Thrust propeller for that 4-HP engine.