boat listing to port???

rcflyers

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I have a Fletcher Arrowsprint 129 speedboat (13ft long) with a Johnson 50 (and doel fins) on the back, I sit on the starboard side and my wife who's lighter than me sits on the port side. At planing speeds the boat leans to the port side quite a lot.
i cannot work out why?
Any ideas please?
 

peterb26

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Presuming the weight of the boat is equally distributed and there are no abnormalities in the hull or prop/fins, then the only thing I can think of is actual prop effect?

The outboard needs to be mounted slightly offset from the centre of the boat to counter this.

However, what little I know about smaller boats has been learnt from Mendez Marine in the last few weeks - so there may be others better placed to help.
 

Lakesailor

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Is this the tab you mean? It only swings left and right and so only adjusts for a prop-walk effect. On my 15ft boat at lower than planing speed the boat was pulling strongly to starboard. Adjusting it (the "wrong" way from what you'd think) has decreased that effect if not totally cleared it.
At planing speed it has always tracked straight.

I would say the first port of call is to try it without the Doel fins. Might be illuminating.
 

Lakesailor

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Ooooerr. If you move the aft tip of the tab to starboard that will push the stern to port and have the effect of steering the boat to starboard. I think.

On the other hand it may be that moving the aft tip of the tab to starboard pushes the leg to port, which would make the boat turn to port.

It all seems different when you're bobbing about in a dinghy and the motor is tilted up.

That's what I mean about not what you would think. I can't remember which was correct /forums/images/graemlins/confused.gif
 

MapisM

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A bit tricky, innit?
In fact, the fin you're talking about is not meant to push the boat, neither port nor starboard... /forums/images/graemlins/smile.gif
It is meant in fact to "push" the leg (which in turn, you may say, will also turn the boat), but that is just to compensate the effect of the prop walk on the steering wheel.
You said in your previous post that your boat "pulled starboard".
Didn't you actually mean that to keep the boat straight, you had to keep the wheel from turning starboard?
That's because the prop walk has also the effect of pushing the leg (hence also the boat) starboard.
By turning the fin starboard (or clockwise when seen from the bottom, just to avoid misunderstandings), you push the leg port to compensate the starboard push of the prop.
The final result is that the leg (hence the boat) keeps a straight course without effort required on the steering wheel.
But the bad news for rcflyers is that this hasn't a lot to see with his problem.
For the type of problem he mentions, I'm afraid there isn't an easy trick to sort it out, and he'd better get it checked by an expert.
 

Lakesailor

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Well. You've said exactly the same as I said.

Except that you say[ QUOTE ]
You said in your previous post that your boat "pulled starboard".
Didn't you actually mean that to keep the boat straight, you had to keep the wheel from turning starboard?

[/ QUOTE ] I meant what I said. If I let go of the wheel the boat went hard starboard. Is there a difference?

The rest of it is precisely what I said.

I also said [ QUOTE ]
It only swings left and right and so only adjusts for a prop-walk effect.

[/ QUOTE ] Which is what you have said.

Can't quite see the point you are making. Are you correcting me by saying the same thing?
 

MapisM

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[ QUOTE ]
Can't quite see the point you are making. Are you correcting me by saying the same thing?

[/ QUOTE ]
Not really, and I apologize if it could be read in such way.

My point was just that a single outboard leads to:
1) tighter and easier port turns
2) starboard pull on the wheel (unless hydraulically assisted, of course).
The leg fin we were talking about is meant to balance the second, whilst there is no solution for the first.

Maybe you said the same thing, but I didn't understand so and thought to throw in my 2 cents...
 

DoubleVision

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The Sprint 129 was only supposed to take a Max 40hp engine. I would say this problem is torque effect from the prop more than anything. I would move the engine 50mm to the right (starboard) and get rid of that stupid fin thing. They get you on the plane quicker which you shouldnt need with an over powered boat and once on the plane cause drag and handling issues. They are designed more for an under powered boat that can only just plane. Hope this helps.
 

landlockedpirate

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The bigger Fletcher hulls have a habit of leaning into the wind or waves. I have never had exprience of your hull but if this is the problem a way to cure it is to trim the engine up when on the plane, this will level the boat out. Of course if you havent got trim and tilt this wont work !!


Mark
 

rcflyers

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I trimmed the outboard out one notch and it was fine today - ran nice and level!

The steering is quite a bit harder to turn to port than to starboard, which way do I need to rotate the engines trim tab to balance it up a bit?
Is it possible to remove an inner teleflex steering cable to clean and lubricate it?
thanks.
 

MapisM

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[ QUOTE ]
The steering is quite a bit harder to turn to port than to starboard, which way do I need to rotate the engines trim tab to balance it up a bit?

[/ QUOTE ]Didn't we cover that already?
Anyway, you should rotate the anode fin clockwise (looking at it from below)
 
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