Flexofold propellor

[2574]

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I have a three blade Flexofold propellor. Good kit but two issues:

1) when engaging ahead (after it having folded) it can be difficult to get the propellor to open up - it is evidently out of balance and it shakes the boat for a while until it opens fully and becomes balanced after which it is fine. Has anyone had similar symptoms?

2) it engages with quite a thump - I wish it wouldn’t. Anybody else have this issue? Engaging astern is much less of a “thump”.

Any experience or guidance gratefully received.
 

[2574]

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I don't have either of these issues with mine. When was the last time you checked the prop by opening and closing it by hand? Maybe something is fouling the cogs on the blades.
It opens and closes absolutely fine, been checked whilst on the hard. This problem has existed for a while, it's liveable with just tiresome. It normally opens up after a few seconds and it's then fine, it's just the initial opening revolutions that seem to be the problem. Does yours open with a noticeable "thud"?
 

sailoppopotamus

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No, not really. Definitely doesn't take a few seconds to open, it opens pretty much instantaneously. Does the thud happen a few seconds after you shift the gear lever? Is it definitely the prop opening or could it be something else in the transmission (e.g. damper plate)?
 

lustyd

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What grease did you put in it? If in doubt call Darglow they’ll get you sorted with good advice
 

[2574]

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No, not really. Definitely doesn't take a few seconds to open, it opens pretty much instantaneously. Does the thud happen a few seconds after you shift the gear lever? Is it definitely the prop opening or could it be something else in the transmission (e.g. damper plate)?
Thud happens as the gear is engaged. I’m pretty sure it’s the prop. When engaging astern there’s not the same issue, only ahead.
 

dunedin

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Our flexofold doesn't do that. Starts instantly and smoothly.
I would do what did with previous boat that had snow issue with a different prop type, and use a cheap endoscope camera to film what happens when put into gear. Readily available on Amazon or similar. Need pole to hold in right place- practice first without propellor turning!!!
 

lustyd

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Oh also, the cutless bearing probably needs replacing and the engine mounts need checking. It’s probably not the prop. Sorry should have opened with that!
 

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hmmmm - forum just seems to have crashed and dumped my reply and created some weird entry. I’ll type again in the morning, thanks for helpful suggestions.
 
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penfold

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1. Don't really understand that; the blades are geared together and can't be significantly out of balance. A close look at your cutlass bearings, engine mounts, flexible couplings etc may bear fruit.
2. Engaging forward drive with folding props can give a bit of a thump in my limited experience, it seems it can be a feature of the product.
 

earlybird

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I have a three blade Flexofold propellor. Good kit but two issues:
1) when engaging ahead (after it having folded) it can be difficult to get the propellor to open up -
That's odd behaviour, because in forward gear, the hydrodynamic forces and centrifugal forces on the blades are supplementing each other, usually making for quick, easy opening. Hence the thump when they do actually open. Astern gear is the opposite of course. I'd be carefully looking for some for some stiffness or similar when the blades are tightly closed, perhaps in the gear system.
 

lustyd

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Perhaps it just needs greasing. I don't grease mine, but maybe I should start doing so.
In hindsight I have no idea. I misread that it's a folding prop which seems to have the gears open to the sea so nothing like the feathering ones with specific grease requirements. I imagine they do need grease but may be different.

I also assumed shaft drive, which I probably shouldn't have!
 

VicS

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What grease did you put in it? If in doubt call Darglow they’ll get you sorted with good advice

Perhaps it just needs greasing. I don't grease mine, but maybe I should start doing so.
The instructions for Flexofold propellers say:-
• The only maintenance required is to keep propeller clean​
.• No need to oil or grease, the parts are water lubricated as soon as in the water.​
.​
 

sailoppopotamus

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The instructions for Flexofold propellers say:-
• The only maintenance required is to keep propeller clean​
.• No need to oil or grease, the parts are water lubricated as soon as in the water.​
.​

Thanks - -that's what I remember reading and chose not to grease when I had the boat out. But yesterday this thread prompted me to search and find this lilnk where Flexofold says that grease may help with opening and closing. At any rate, I can't see how it could hurt.
 
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