In or out of gear?

Depends on gearbox manufacturer ... some say in ... others say def. out.

Mine - I don't know and leave mine out.

[edit] I have just checked my worskshop manual for my PRM Gearbox .. it says quite clearly in its own section ! :

PRM Gearboxes are designed and tested to ensure that prolonged periods of trailing (free-wheeling) the propellor are permissible without any detrimental effect to the transmission. It is not therefore necessary to provide any propellor shaft locking device.

I would assume as the gearbox is hydraulic - it would be difficult to stop it spinning anyway ...
 
Volvo saildrive ... the book says don't lock. No idea why. Annoys me because at 7-8 knots I can feel it turning.
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A boat probably spends more time moored or at anchor than under sail, and might well be experiencing current flow equivalent to sailing. So you leave the gear permanently engaged, if that is the advice when sailing?
 
PRM ? as mine ?

Way to do it - as per PBO Hints book - bicycle caliper brake !! on the shaft.

Just don't forget to release before putting in gear.
 
Yep. Fixed two bladed on a 2020 engine.

Would love to know what would happen if I did lock it. At speed I get a slight vibration as it spins .... not a problem round The Solent but was a bit irritating on a high speed 200 mile blat back from France this year.
 
We have a 2030sd and it was another reason to buy a feathering Kiwi prop. Keeping the fixed prop spinning made an annoying hum and if you read instructions carefully, volvo recommends truning on the engine from time to time to lubricate the gears!

All problems solved with the Kiwi, and the boat goes faster under sail and engine.
 
My gearbox is a Hurth, which is amechanical box with metal friction disks running in automatic transmition oil (Dexron), so I always set mine in reverse when sailing. Part of the joy of sailing is not having the noise of the engine, or the whining prop shaft. Also I seem to remember on item in PBO where it was said that a spinning prop generates more drag than a locked prop. the reason I engage reverse is that in my cockpit the lever less in the way in reverse than forward, although I am sure forward would be just as good.
 
[ QUOTE ]
a spinning prop generates more drag than a locked prop.

[/ QUOTE ] Yet to have empirical evidence on this one. I suppose it depends on the prop and the boat speed, but it's not a given.
 
The spinning prop argument ...

Boats, model planes, various where a prop is fitted - there are large groups that say to stop it spinning - based on the spinning prop is creating a disc instead of just blades.

I was convinced while flying models and still feel the spinning prop is more drag - but cannot like the stopped prop people produce actual evidence for it.
It's academic for me anyway - can't stop my prop turning unless I fit a shaft brake !
 
Now that's an idea, and I can borrow one to try off the Soup-Dragon's bike without investment problems. She might be confused by the handbrake-type ratchet on the lever if it ever gets back to the bike though....
 
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