Prop Rotation

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Drago

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Joined
Mar 6, 2018
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28
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United States
Does anyone know what the prop rotation is on a Marine Trader 40 Sundeck with twin Volvo Penta TAMD 40 B's?
 
Twins almost alway turn their props outward from the center of the hull, so looking from back end, port prop turns ccw, starboard tuns cw.
And the trans most likely can turn either way, except for most older velvet drives which the engine has to turn one way or either depending on port or starboard use.

Use to be gas engines would turn either ccw, or cw, today gas and diesel all turn the same and the trans makes the spin difference.
 
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Most twin screw boats have a right hand on stbd and left hand on port. RH prop rotates clockwise when viewed from aft in fwd gear.
 
How old is your boat?
On my 1980 C&L 44 (looks like a MT44), that came to me with the same engines as yours, the transmissions do the reversing, so with both engines turning the same way, the port prop, walks the boat to Stb in reverse and the Stb prop walks it to Port in reverse. Just think of a wheel on the pavement, when it turns clockwise (viewed from astern) the boat will move to Stb, and vice versa. I have heard of folks with twin outboards, though rare, having both turning the same direction, but never with shaft drive.
To check, just put one in reverse and watch for the prop walk.
 

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