LH or RH Propeller Drive Unit

vegaschef364

Cadet
Joined
Jun 24, 2022
Messages
26
I am trying to adjust the shift cable on my Alpha1 Gen1. When facing the drive from behind, the prop locks ccw in forward and cw in reverse. I have a Merc service manual #6 and under the Propeller Rotation section it says when viewing from aft end of prop, RH rotation turns clockwise, and LH turns ccw, those are both forward gears, correct? So forward on a LH rotating prop drive is ccw, and forward on a RH rotating prop drive is cw? But later on in the manual under the shift cable adjustment section it says for a LH propeller rotation drive unit, shift remote control into forward gear wot while rotating prop shaft cw to engage forward, shouldn't it say ccw? Am I misinterpreting what is written there? Also, I keep seeing people stating standard rotation, which one is standard, RH or LH?
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
38,482
A right hand unit ( in forward ) would LOCK turning the prop CCW and it would ratchet turning CW.
 

vegaschef364

Cadet
Joined
Jun 24, 2022
Messages
26
Is that standing behind the boat? This is what my manual shows. RH is cw and LH is ccw viewing from the aft end of the propeller. I assumed it was viewing it from behind the boat, but maybe they meant standing on the back of the boat? Or is it a typo?
 

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johnkom

Petty Officer 2nd Class
Joined
Jul 26, 2004
Messages
180
Years ago when I started working on these drives that confused me too. But you have to think what the prop is doing in the water. On a RH rotation when in forward the engine is trying to turn to the right and the water is resisting pushing back to the left. So you can't turn it left because you're resisting the engine. The engine torque is to the right and the water resistance is to the left. So unless you are stronger than the engine, you can't turn the prop left (CCW.)
 
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