Stopping prop from turning while moored.

[pcatterall]

And another thing!! at around 2.5kn the prop turns when moored. Them lot int 'back bedroom' complain about their beauty sleep ( lack of ).
I can't think of a good reason why it should not be stopped ( slightly more drag I suppose).
Any known objections and how would one do it?

 

[Corribee Boy]

Leave it in gear? It might be worth checking the manual, as my Hurth gearbox specifies locking in reverse, or expensive damage results!

 

[Frankie-H]

If you have a mechanical gear box that will work. If you have a hydraulic gear box it won't. If that is the case, then try tying a pole or stick to the shaft with a rolling hitch.
Don't forget to take it off before you go sailing,

 

[Chalker]

Careful, or you will re-start the debate as to which creates more drag; a spinning or locked prop!!

 

[Seajet]

If putting any sort of disabling device on the shaft, I'd strongly suggest a red ribbon or similar on the engine controls, similar to aircraft practice of 'remove before flight' tags on disarming / locking pins.

Another option might be to put the ignition key on the ribbon leading to the disabler.

Otherwise it's just a matter of time before one turns the key or presses the starter and hears a " what the **** was that ?! " expensive & inconvenient sort of noise...

 

[Hoolie]

And if you're still having problems with "them lot", put them up in the fore cabin!

 

[sarabande]

in extremis, a big Mole Grip works. But don't forget the above mentioned red robin.

 

[Seajet]

And if you're still having problems with "them lot", put them up in the fore cabin!

Ah, but then 'them lot' will moan about the mooring grumbling & rumbling on the seabed, or the chain rattling & snatching in the bow roller...

As for drag OK I'll bite; I believe it has been proven that a stopped prop incurs less drag than a freewheeling one, which acts pretty much as if one was pulling along a full disc the size of the prop diameter; also trundling along in neutral with the prop spinning wears things out.

 

[sailorman]

And if you're still having problems with "them lot", put them up in the fore cabin!

Then theres them blimmin chains clanking all nite

 

[DaveS]

Ah, but then 'them lot' will moan about the mooring grumbling & rumbling on the seabed, or the chain rattling & snatching in the bow roller...

As for drag OK I'll bite; I believe it has been proven that a stopped prop incurs less drag than a freewheeling one, which acts pretty much as if one was pulling along a full disc the size of the prop diameter; also trundling along in neutral with the prop spinning wears things out.

Not wishing to start off this old chestnut again, but I don't think the point re comparative drag is right. I agree with added wear, however. More relevantly, if a feathering prop is fitted the problem is eliminated.

 

[Deleted member 36384]

Leather and Mole Grips

in extremis, a big Mole Grip works. But don't forget the above mentioned red robin.

Perhaps not just in extremis. I use mole grips to stop my prop rotating when sailing (BorgWarner Hydraulic Gearbox). I use a section of leather from an old belt, about 6 inches long and clamp the shaft by applying the grips over the leather.

The method is very easy: with the propellor shaft rotating freely I feed the belt round the shaft and pinch the top sections together while pulling the looped part tight against the shaft (which continues rotating). I then offer up the mole grips to the stationary leather and close them. As the mole grips tension increases and squeezes the leather the prop shaft slows down and stops. Make sure that the mole grips come to rest against a bulkhead or floor.

The beauty of the leather is that if the engine is started with the mole grips attached the shaft will still turn, easily overcoming the friction.

I got this tip from a forumite.

 

[sailorman]

Perhaps not just in extremis. I use mole grips to stop my prop rotating when sailing (BorgWarner Hydraulic Gearbox). I use a section of leather from an old belt, about 6 inches long and clamp the shaft by applying the grips over the leather.

The method is very easy: with the propellor shaft rotating freely I feed the belt round the shaft and pinch the top sections together while pulling the looped part tight against the shaft (which continues rotating). I then offer up the mole grips to the stationary leather and close them. As the mole grips tension increases and squeezes the leather the prop shaft slows down and stops. Make sure that the mole grips come to rest against a bulkhead or floor.

The beauty of the leather is that if the engine is started with the mole grips attached the shaft will still turn, easily overcoming the friction.

I got this tip from a forumite.

WOT you need is a MaxProp

 

[RobbieW]

Having suffered a line wrap around the prop whilst overnighting on a bouy in Langstone Harbour entrance, I'd say find a way to stop it turning!

 

[Deleted member 36384]

WOT you need is a MaxProp

That would be nice but not yet worth it, perhaps when my trousers fall down,

 

[sailorman]

That would be nice but not yet worth it, perhaps when my trousers fall down,

mine often do now

 

[Tranona]

Everybody seems to be missing the point. The OP is wanting to stop the prop turning at anchor (presumably the current doing it). Simple if it is a mechanical gearbox, put it into reverse. If it is hydraulic then a shaft brake is required (which could be a mole grip if you remember to remove it before you start - keys attached to the grips?)

 

[Deleted member 36384]

Everybody seems to be missing the point. .....

Au contraire! The OP question is well and truly answered with examples of how others stop the prop shaft from rotating.

 

[misterg]

And if you're still having problems with "them lot", put them up in the fore cabin!

Then theres them blimmin chains clanking all nite

What on earth are they up to?

 

[Spyro]

Presumably you cant stop it when sailing or you wouldn't be asking the question. So would it be possible to jam a small wooden stick against the gearbox coupling, then if you forget to remove it it will just break.
I also like the mole grips around leather idea.

 

[onesea]

IN the camp of stop it turning when sailing or stopped here, but bad memory in remembering to remove....

What I have use in the past is an old bike inner tube secure one end to something solid, create a riding turn on the shaft wait for it to stop.

If you make the mistake £3.50 for the spare inner tube caried for the next time