Neutural or Reverse?

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Jeff75

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Dec 9, 2007
24
Catalina 310 Niagara on the Lake
Neutral or Reverse?

Just wondering what the general train of thought is for the positioning of the transmission when under sail. I have had people tell me both "leave it in neutral" and "put it in reverse".

I have not been able to find any specific direction from the manual. We have a Universal M-XP25.

Thanks in advance
 
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MarkZ

MarkZ

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Nov 5, 2005
119
Hunter 49 Green Turtle Bay: Ky
I always put mine in reverse. And I vaguely remember reading that somewhere. Maybe it was in the manual for the transmission. If I remember right it said exactly what is on the red tag in the link that PaulJ provided above.
 
rpwillia

rpwillia

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Sep 29, 2008
1,944
Catalina 310 #185 Quantico
The Universal Manual says ...

For Yanmar transmissions, they recommend pretty strongly that when sailing you leave your transmission in reverse. This is because when the engine is not running there is no lubrication going to the thrust bearing. The Universal Mx-25 XPB uses a Hurst HBW 150 transmission that has lubrication at the thrust bearing all the time. Here is a section out of the Hurst HBW 150 manual that speaks specifically to this issue.

[FONT=&quot][/FONT]When under Sail or Being Towed

Rotation of the propeller without load such as when the boat is being sailed, being towed, or anchored in a river, as well as operation of the engine with the propeller stopped (for charging the battery), will have no detrimental effects on the transmission.
That being said, most of the time I leave mine in reverse when sailing as it is just a little quieter. Occasionally, if I am racing I will leave the transmission in reverse, but there was a lonnnngggg thread in the Ask All Sailors forum about the benefits, and I believe it was determined that it caused more drag to have the prop spin, especially if you have a 3 bladed prop like I do.
 

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J

Jeff75

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Dec 9, 2007
24
Catalina 310 Niagara on the Lake
Thanks all,, for your input,,,,very informative as usual,,
 
Witzend

Witzend

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Dec 25, 2008
1,580
catalina 310 Elk River
It's hard to believe that the force of the water on a prop sailing at 6 knots could trun the a engine over in forward. I'm going to see next time I'm out.
 
MarkZ

MarkZ

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Nov 5, 2005
119
Hunter 49 Green Turtle Bay: Ky
I don't think anyone here is trying to say that the force of the windmilling prop would turn over the engine. I think the reason most transmissions suggest using reverse rather than forward is because it reproduces the same forces on the clutch as there would be if the engine was driving the shaft. If sailing with the transmission in forward then the load on the clutch is opposite the intended direction.

There's not doubt that a windmilling prop produces more drag than if stationary. Also, why let parts move and thus cause wear unnecessarily.
 
Witzend

Witzend

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Dec 25, 2008
1,580
catalina 310 Elk River
What clutch, Direct drive, if it doesen't turn it won't wear.
 
MarkZ

MarkZ

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Nov 5, 2005
119
Hunter 49 Green Turtle Bay: Ky
I'm not sure what you're trying to say, Witzend. The clutch is the assembly (in the transmission) that engages and disengages the prop shaft from rotating whenever we operate the shift lever. Our props are not direct drive...the transmission gets in the way of that. In fact, if I remember right they're even geared down 2:1.

"If it doesn't turn it won't wear" is exactly my point and thus one good reason to keep the transmission engaged while sailing- less drag is another good reason.
 
Witzend

Witzend

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Dec 25, 2008
1,580
catalina 310 Elk River
So you're saying that the lever to engage the transmission operates a clutch and engages it in gear as well. Don't know why there would be a need for a clutch, just synchronizers to get it gear, were not driving a wheel on a stationary surface. Do you have an exploded view of the Hurst HBW 150?
I improperly used to term "Direct Drive". When I indicated direct drive I did not mean there was not a gear set involved.
My point here is common sense tell me that forward or reverse it will not turn the prop @ 6 knots.
 
MarkZ

MarkZ

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Nov 5, 2005
119
Hunter 49 Green Turtle Bay: Ky
I'm talking about a clutch in it's most generic term. Not necessarily one that works by way of friction as you would find in a manual automobile tranny.

Here is a link to a view that is difficult to read:
http://www.marinedieseldirect.com/c...&title=BELL HOUSING AND TRANSMISSION&size=800

I agree completely that there is no way that 6 knots through the water will turn over the engine. I didn't realize that anyone thought it would. But many transmissions state specifically to use reverse and not forward. And I'm assuming the reason is to keep the load on all the parts going in the same direction as if the engine was driving the movement.
 
Witzend

Witzend

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Dec 25, 2008
1,580
catalina 310 Elk River
Not sure if we have the 1:9:1 or the 2:1 but in any event the blow out view does not break down what is in the tranny. Not sure what other kind of clutch there is other than a torque converter on an automatic. Reverse would put the load internally to the tranny as if it were delivering it, but since the output of the tranny is designed to deliver torque in both directions, not sure it would really matter.
 
P

paulj

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Mar 16, 2007
1,361
Catalina 310 Anacortes,Wa
Here is another opinion........

http://www.foleyengines.com/FreeTechnicalInfo/DrDieselShopKinks/Hurth-Gear-Shift-Position.aspx


When sailing I keep the transmission in neutral.
When boat is in the slip resting I keep the transmission in neutral.

After doing some reading on the HBW-50 if I was to do something, I would put in a flex coupler like Ray did.

How long do you think the HBW-50 transmission should last of course taking resonable care.........
Use engine hours, sailing hours, total time in boat ????


paulj :troll:
 

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Witzend

Witzend

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Dec 25, 2008
1,580
catalina 310 Elk River
Where are all the wires and hoses? On my C310 to even see the coupling you have to be a contortionist. So, we have the HB-50 not 150? Not sure life expectancy. Great link for tech tips, thanks.
Tom
 
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paulj

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Mar 16, 2007
1,361
Catalina 310 Anacortes,Wa
If you need a quote to make things fall into place and for you to feel better and justify your position....

If you hit a log or something while sailing with the transmisson in neutral you would just spin the prop.


But with....................


From the gang at the dock tonight.


paulj :troll:
 
C

Calif. Ted

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Jun 8, 2004
2,952
Catalina 320 Dana Point
So far I have 900 hrs. on a HBW-50 out of about 8000 logged miles with the trans in reverse. I think if you hit a log at 6 knots it really isn't gonna matter what gear it's in, it ain't gonna "just spin the prop".
 
jonfreeman

jonfreeman

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Jan 22, 2008
106
Catalina 350 Tacoma, WA WA
On my boat, I have an AutoProp, and the recommendation for that is to put the lever in FORWARD, so the prop will fold.

Incidentally, on this AND on my 350 (previous boat), NOT putting the boat in gear while sailing meant the prop and transmission would freewheel, and make the STRANGEST noise approximating a moan. Kinda spooky, until we figured it out :)

Jon Freeman
C-310 "Summer Sojourn"
Seattle/Tacoma
 
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