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  #1  
Old 01-22-2006, 06:31 PM
backhoebob backhoebob is offline
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outboard not long enough

I have a 1988 mawum 20' with a 150hp blackmax outboard that is about 3 to 4" to short the cavition plate is 3 to 4" above the bottom of the boat and not getting a good bit in the water, any ideas on how to fix this problem with out buying a new motor maybe a jackplate will work???
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Old 01-23-2006, 04:44 AM
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yipster yipster is offline
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have to check but think for 150 hp you can get a long tail also, not a cheap conversion tho.
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Old 02-22-2006, 04:36 AM
meren meren is offline
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With 1 foot setback the rise of cavitation plate (above keel line) is about 1 inch depending on deadrise angle and propeller type.
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Old 02-24-2006, 07:39 PM
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gonzo gonzo is offline
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You can cut down the transom.
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  #5  
Old 03-03-2006, 05:22 AM
hmattos hmattos is offline
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Here at Explorer Marine - www.explorermarine.co.uk - we have worked on some boats where the rear 18" 500mm of the hull is cut up on a concave curve from the keel to allow a 20" outboard to be used on a deep vee hull. Works very well, and saves the cost of a 25" extra long shaft.

During fast acceleration you will find a little more bow lift unless you have the engine trimmed well in and a good 12 degree or more? transom angle.

Good Boating
Hugh Mattos
C.Eng.M.I.Mech.E.
Explorer Marine
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  #6  
Old 03-06-2006, 09:52 AM
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dereksireci dereksireci is offline
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Don't do it.

Quote:
You can cut down the transom
Not recommended for several reasons.



Quote:
I have a 1988 mawum 20'
What's a mawum?

djs
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