The type of prop and reduction gear (transmission) makes a difference between 
sailing in gear or not.

A fixed prop will often cause the shaft to spin resulting in damage from lack 
of lubricant.  Some boats have a shaft brake installed.

A folding prop will rarely cause the shaft to spin.

A feathering prop will likely need to be stopped in gear (engine running with 
some reduction gears) to hold the shaft long enough for the blades to feather.  
A sticky feathering prop may induce shaft rotation.  Some boats have a shaft 
brake installed.

On Calypso with a 3 blade MAX Prop and a Borg Warner velvet drive reduction 
gear we get the boat up to speed (4 to 5 knots typically) and shut the engine 
off in gear.  When sailing, with the prop feathered we leave the reduction gear 
in reverse to keep the shift lever out of harm's way.  The reduction gear being 
hydraulic will not lock the shaft but once the prop is feathered the shaft does 
not rotate.

I recommend you follow the owner's manual regarding the in or out of gear 
selection.  If you hear the sound of the shaft spinning it almost always 
indicates some action is necessary to prevent damage from lack of lube.

Martin
Calypso
1971 C&C 43
SEattle
________________________________
From: [email protected] [mailto:[email protected]] On 
Behalf Of Rich Knowles
Sent: Thursday, September 06, 2012 10:09 AM
To: [email protected]
Subject: Re: Stus-List Martec Folding Prop Operation

Just read the advisory note. Interesting. Other transmissions don't like the 
shaft turning when the engine is off as the tx oil pump runs off the input 
shaft and lubrication stops when the engine stops.

Rich
Rßdë
On 2012-09-06, at 13:05, Joel Aronson 
<[email protected]<mailto:[email protected]>> wrote:
With a fixed prop you are putting pressure on the bearings to turn the shaft 
the other way.  I would think that you are also increasing drag.
Didn't seem like a big deal to me until I found out it voids the warranty.  
Either Yanmar is looking to reduce warranty liability or there is really 
something there.
Joel
On Thu, Sep 6, 2012 at 12:00 PM, Rich Knowles 
<[email protected]<mailto:[email protected]>> wrote:
Why can you not sail with the gear box in reverse?  I e done that for years to 
keep the shaft from spinning when underway and trashing the bearings in the tx.

Rich

On 2012-09-06, at 12:38, Joel Aronson 
<[email protected]<mailto:[email protected]>> wrote:
My Martec will vibrate if it is not in the right position.  I put the gearbox 
into reverse for a second or two and the vibration stops.  I assume it is in 
the feathered position.  (Don't sail with the gearbox in reverse.)

Joel
35/3
The Office
Annapolis


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