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Old 27 October 2004, 22:24   #1
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twin engine ??

Howdy Gang,
I was wondering about the prop rotation on outboards in a twin engine set up.
Are they set up to spin in opposite directions?

Which side would have the right hand wheel and which would have the left?

Can one engine be run in reverse ?

BTW the motors are Honda 45's


thanks
hank
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Old 28 October 2004, 03:07   #2
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"Which side would have the right hand wheel and which would have the left?"

HI port engine runs anticlockwise & starboard runs clockwise, as you look from behind!


"Can one engine be run in reverse ?" yes great for maneuvering!

Nick
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Old 28 October 2004, 03:56   #3
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Are you talking about putting a left handed prop on and running the gearbox backwards? As opposed to a proper contra rotating unit?
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Old 28 October 2004, 06:34   #4
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Props

Quote:
Originally Posted by hank
Howdy Gang,
I was wondering about the prop rotation on outboards in a twin engine set up.
Are they set up to spin in opposite directions?

Which side would have the right hand wheel and which would have the left?

Can one engine be run in reverse ?

BTW the motors are Honda 45's


thanks
hank
Hi Hank,

Ideally, if the machinery allows it, you would want to have a right hand rotation propeller (clockwise when going forwards) on the starboard engine and a left hand rotation (anti-clockwise when going ahead) on the port engine. This allows for the best maneouverability and dynamic stability.
You could put them on the other way round and this "may" give more speed but may also be less stable.

Unfortunately very few outboard gearboxes can be run anticlockwise for extended periods without damage unless they are specifically "counter rotation".

Therefore I think that with the Hondas you will probably have to run right hand propellers on both engines.

Regards
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Old 28 October 2004, 08:28   #5
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Honda 45 are too small for counter rotation... it only when you get over a 100 Hp or so, it becomes an issue ...

We run twin 75's , same rotation.. no problems... on a flat day you have to trim one of the engines slight to allow for a slight lean caused by rotation...
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Old 28 October 2004, 12:35   #6
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Hi Again,
Your replies made my job a lot easier.

We will just use the Honda's as is and see how it goes.

Thanks
hank
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