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Old 12 April 2011, 05:16   #11
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Hmmmm. It's an expensive test if you don't have a bent prop. Have you given any thought to our suggestions above? - i.e. trim tab adjustment or engine trim position?
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Old 12 April 2011, 12:06   #12
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Yep, I'll second Will on that..... You sure your mate didn't also put it in for a servicce at the same time or the dealer tweaked the trim tab whilst testing it?


Basically 4 blade = more grip + more drag. Unless you are pushing a barge along I wouldn't bother on a 40.


What prop you got now? I have a merc 10.? x 13" and a Yam 10.<a bit more than the Merc one> x 14" if you want to try, but I doubt it will make much difference to the steering. Is your prop nut held on with a split pin or a tab washer?

I'd try the trim first - it;s a free test .... if you ignore the burnt fuel!
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Old 14 April 2011, 08:46   #13
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what way should i adjust the trim tab?
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Old 14 April 2011, 10:30   #14
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Not at all unless it pulls to the left or the right!

I meant trim as in "in/out" - moving the pin that goes through both clamps that it rests against when fully down.


Item 23 on this (totally random) pic
http://www.boats.net/parts/search/Me...KET/parts.html
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Old 14 April 2011, 11:09   #15
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ok. It is all the way down so i should move it up one notch
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Old 14 April 2011, 11:22   #16
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Quote:
Originally Posted by chrishowden View Post
ok. It is all the way down so i should move it up one notch
Might be easier than moving it down a notch !!
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Old 14 April 2011, 11:41   #17
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Might be easier than moving it down a notch !!
Cheeky - we're all being very patient here and you go and spoil it

Yes Chris, try moving it up one (maybe two notches) first and try the rib at your "crusing" speed. Try a turn or two and see how it feels (steering wise). If the prop cavitates too readily, you'll have to come down a notch again. It's a trade off between light steering and prop cavitation. (ok, ventilation, i no, i no )

On the up side, you'll find that your top speed has improved and you'll use less gas. However, the higher you set the trim, the higher the chance of cavitation on "takeoff" and in turns.
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Old 14 April 2011, 11:49   #18
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Quote:
Originally Posted by willk
If the prop cavitates too readily, you'll have to come down a notch again. It's a trade off between light steering and prop cavitation. (ok, ventilation, i no, i no )

... the higher you set the trim, the higher the chance of cavitation on "takeoff" and in turns.
Why are you calling it one thing when you know it to be another?
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Old 14 April 2011, 11:55   #19
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Why are you calling it one thing when you know it to be another?
'Cos someone will correct me no matter which I use.

(or ask me why )
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Old 14 April 2011, 12:09   #20
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'Cos someone will correct me no matter which I use.

(or ask me why )
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