Lock the prop or let it spin? 386

Nov 14, 2016
17
Hunter 386 QCYC
Hello folks,

We have a new-to-us 2002 386. Under sail, we lose a full knot when the prop is locked. When left to spin, we are far faster. So, what I want to ask is:

  • Does anyone else record this outcome?
  • My owner's manual does not tell me if it should be locked or free,
  • or am I missing something and ought to pull the transmission engage button;
  • Is there is a problem with the 386 in letting the prop spin? That is, do I need the engine lubrication?
  • When I let it spin though, there is vibration and a whub-whub-whub under sail.
Its a full knot ... I need that speed!!

Thanks
 
Feb 17, 2013
53
Hunter 380 Port Clinton, Ohio
I have a 2000 Hunter 380. I removed a feathering Max Prop and installed a 3 blade Flex-o-fold prop. Solves all of your present issues. And I can back out of my slip to starboard or port with ease.
 
May 24, 2004
7,129
CC 30 South Florida
Yanmar recommends you let the prop spin in neutral. The transmission is self lubricating as it spins the gears. Wear and tear is minimum as proven by a long history of usage. It will also reduce the significant drag induced by a locked prop.
 

jviss

.
Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
I don't like the noise, so I put the gear in reverse when sailing. Note that with a two-blade prop, there are some better positions, like up and down, than others, for drag. Also, with a Maxprop or other feathering prop, putting the gear in reverse will make the prop feather, which is a very low drag configuration.
 

Gunni

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Mar 16, 2010
5,937
Beneteau 411 Oceanis Annapolis
See Ralph's post of the YANMAR advisory. In fact, placing a MaxProp into reverse transmission position locks open the blades, driving the shaft (and transmission). There are limited uses for that if you have a shaft generator, but on a YANMAR you have to disconnect the shaft from the transmission or you will lunch the transmission. For MaxProp shut down in forward to feather then move the transmission to neutral. She won't spin.
 
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Likes: jviss

jviss

.
Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
Thanks, Gunni!

But I just checked the manual, and found this:
The MAX PROP® Max-prop works automatically. By putting the engine in gear the blades will

engage in either forward or reverse. The best way to feather the propeller is:

• Power at 2 to 3 knots in forward.

• Kill the engine while still engaged in forward.

• When the engine has stopped, if the shaft is still spinning engage the transmission in reverse

to stop the freewheeling.

You can check to see if the propeller is feathered or not by taking the engine out of gear. If the

propeller is not feathered the shaft will freewheel like with a fixed blade propeller. In that case

start the engine again and repeat the three steps. If your propeller has been greased properly it will

feather in a fraction of a second as soon as you stop the shaft from freewheeling. Once the prop

is feathered, you can either leave the transmission in gear or out of gear, it does not matter. DO

NOT kill the engine while in reverse. In this case the blades will be in the reverse position and will

not feather. You can actually use this feature to drive a shaft alternator.

IMPORTANT: If the MAX PROP® is installed on a vessel that can attain sailing speeds over 15

knots, it is MANDATORY to return the transmission to neutral while sailing. If the transmission

remains engaged and the propeller were to open (from hitting an object or water flow) it may turn

the engine, flooding it, resulting damage to the engine.
[/QUOTE}
 
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Gunni

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Mar 16, 2010
5,937
Beneteau 411 Oceanis Annapolis
Yes, read it carefully. Stopping in reverse may stop the shaft from freewheeling but only because it is loading up your transmission friction cones or clutches. They require the transmission to be operating to get lubrication and prevent wear. Never lock a yanmar transmission in gear to stop it from freewheeling. Either let it freewheel or pony up for a feathering/folding prop.
 
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Nov 14, 2016
17
Hunter 386 QCYC
Wow. Thank you everyone for the responses. Much appreciated.

Got my knot back!

Almost all my friends at my club state that it should be in gear so that the transmission does not burn out. This is excellent advice and direction.

Thank you all.

Hamish
 

jviss

.
Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
Yes, read it carefully. Stopping in reverse may stop the shaft from freewheeling but only because it is loading up your transmission friction cones or clutches. They require the transmission to be operating to get lubrication and prevent wear. Never lock a yanmar transmission in gear to stop it from freewheeling. Either let it freewheel or pony up for a feathering/folding prop.
Gunni, maybe I'm not following you. As I read it, putting the gear in reverse is just a temporary measure to get the Maxprop to feather. Once it feathers, or you think it has, you shift to neutral, and the shaft shouldn't be spinning. They don't say to stop it in reverse, they say kill the engine while still in forward. And, the Maxprop is a feathering prop!
 

SG

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Feb 11, 2017
1,670
J/Boat J/160 Annapolis
That should be the procedure with a feathering prop. Stop engine, put it in reverse momentarily, the shaft will feather, you should then put it back in neutral (only to avoid trying to start it in reverse).

Aside from stopping the noise/vibration, and damaging the transmission, you'll go faster ( I think)
 
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Gunni

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Mar 16, 2010
5,937
Beneteau 411 Oceanis Annapolis
The MaxProp does not feather in reverse transmission position. Period. It only feathers from a stop in forward. Period. I'm starting to understand how so many Kanzakis end up in the shop and why yanmar had to put the procedure in writing.
 
May 1, 2011
4,190
Pearson 37 Lusby MD
Mine does. I put the transmission in neutral, shut the engine down, then put transmission in reverse. Feathers every time.
 

SG

.
Feb 11, 2017
1,670
J/Boat J/160 Annapolis
Mine too, Gunni. If put the transmission in neutral without feathering the prop, it will usually continue to auto-rotate (because the blades haven't reset). Simply popping it reverse (after the engine has stopped) feathers the Max Prop. Then, as pointed-out, I simply return the transmission lever to neutral.

Some non-conventional, hydraulic transmissions might be different?
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Unlike Yanmar, Volvo's need to be placed in reverse per the factory. straight prop or folder.

The difference between the two is the big reason for this misunderstanding.
 
Jul 27, 2011
4,989
Bavaria 38E Alamitos Bay
Unlike Yanmar, Volvo's need to be placed in reverse per the factory. straight prop or folder.

The difference between the two is the big reason for this misunderstanding.
Having just gotten off sailing a charter boat w/ a 78-hp Volvo, the setting is evidently optional according to the documents aboard-can either let it spin in neutral while sailing, or lock it in reverse. It appears to be a matter of whether or not one wants to curtail the sound of the spinning prop.
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Having just gotten off sailing a charter boat w/ a 78-hp Volvo, the setting is evidently optional according to the documents aboard-can either let it spin in neutral while sailing, or lock it in reverse. It appears to be a matter of whether or not one wants to curtail the sound of the spinning prop.
That's possible I suppose. My original Volvo manual says reverse. Which is good because my flexofold likes that.