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Catalina/Capri 25/250 Sailor's Forums

General Sailing Forum

Prop movement

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John Russell
Master Marine Consultant

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USA
3444 Posts

Initially Posted - 08/02/2011 : 09:08:28

I don't tilt my prop out of the water while sailing. The gymnastics to accomplish that requires a much younger and taller man. I lift it using my Garhauer lift but the TOP of the prop is just barely above the water.

I was sailing today enjoying a quiet downwimd run with the exception of the prop spinning and breaking the surface of the water. The motor was off and in neutral. That leads me to my question: Should I leave it in neutral and put up with the noise or put it in reverse and listen to a slightly quieter and less irritating noise? If I put it in forward, it continues to spin and makes a wierd clicking noise. My question is really about wear on the motor. Am I causing more wear by letting it spin or by leaving it in gear.

John Russell
1999 C250 SR/WK #410
Bay Village, Ohio
Sailing Lake Erie
Don't Postpone Joy!

Edited by - on

Stinkpotter
Master Marine Consultant

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Djibouti
9081 Posts

Response Posted - 08/02/2011 : 09:37:36

I've heard/read assertions that a spinning prop (submerged) creates more drag than a locked prop. Inboard sailors lock their props to avoid lubrication problems in the transmission--otherwise the oil circulated by the input shaft is not circulating to the spinning output shaft bearings. I doubt that applies to outboards...

When we were "sailing to nowhere", we sometimes left the bracket down and the outboard in neutral--the boat still moved. You cold try that in neutral and reverse and see which slows the boat more, and then decide whether you care.

Edited by - on

Renzo
Admiral

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USA
621 Posts

Response Posted - 08/02/2011 : 10:48:20

<blockquote id="quote">quote:<hr height="1" noshade id="quote">...requires a much younger and taller man.<hr height="1" noshade id="quote"></blockquote id="quote">
John, I'm not being jugemental, but I don't understand the "taller" part. I'm avarage height and I'm able to tilt my 9.9hp motor from a sitting position.

Edited by - on

John Russell
Master Marine Consultant

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USA
3444 Posts

Response Posted - 08/02/2011 : 12:16:19

Renzo, I'm 5'4" on a real good day with shoes on. The C250 also has the added issue of the cat bird seats. The Tohatsu release mechanism is on the outer side of the motor, Then there's the 98 pounds while hanging fully extended over the transom, etc, etc, etc.

I'm open to suggestions.

Dave, I have noticed that Kaija sails noticeably better on a starboard tack. That lifts the motor higher. I think I'll try it in reverse from now on. The reason I haven't been doing that was so I wouldn't have to remember to shift to neutral so the motor will start. I hate that sinking feeling when you hit the starter button and there's no response.

Edited by - on

delliottg
Former Mainsheet C250 Tech Editor

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USA
4479 Posts

Response Posted - 08/02/2011 : 12:35:42

John,
There was a thread a while back about a mod to the tilt mechanism that makes it simpler. I'm pretty sure it was by Frank Farmer, but basically he rigged two lines to the tilt lever to the underside of his catbird seats that allowed him to control the tilt & release of the lever. I did something similar with a piece of bungee cord that makes it very easy to tilt the engine up, I basically just have to grab the rear of the engine cowling and pull. If I want to put it into the low water position, I just have to reach around (which is a stretch, but I'm 6'-2" so it's not too bad). To tilt back down into the water, I just have to tip the engine up, which allows the bungee to release the catch for me, and tilt back down.

I also noticed the much slower speeds while on port tack this past Saturday when we were sailing on just the jib. We generally leave the OB all the way down and in neutral, which would add more drag on the starboard side. However, I'm willing to put up with the added drag for the ability to be able to immediately scoot out of the way of the various barges, ferries, cruise ships, etc. that populate the bay we sail in.

Edited by - on

Dave5041
Former Mainsheet Editor

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USA
3758 Posts

Response Posted - 08/02/2011 : 12:52:43

I think you should check with Tohatsu online or the service manager at a tohatsu dealer in person or phone and do what is best for the motor.

Edited by - on

Renzo
Admiral

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USA
621 Posts

Response Posted - 08/02/2011 : 16:15:45

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by John Russell
 Renzo, I'm 5'4" on a real good day with shoes on. The C250 also has the added issue of the cat bird seats. The Tohatsu release mechanism is on the outer side of the motor, Then there's the 98 pounds while hanging fully extended over the transom, etc, etc, etc<hr height="1" noshade id="quote"></blockquote id="quote">
C-250 with Cat-bird seats-Now I understand.

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frog0911
Master Marine Consultant

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USA
1349 Posts

Response Posted - 08/02/2011 : 17:27:31

I am a small fellow also, but no problem lifting the motor. Here is my fix. The spring holds the handle down and I attached a line from the lever to the catbird seat. You pull the line and motor, release the line and when the motor is up the spring pulls the lever down an locks it in place. To lower, pull up on the motor slightly, pull on the line and release the motor. Once down release the line.

Edited by - on

John Russell
Master Marine Consultant

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USA
3444 Posts

Response Posted - 08/02/2011 : 18:09:19

Thanks, Frog. Any photos showing the routing and attachment of the line?

Edited by - on

frog0911
Master Marine Consultant

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USA
1349 Posts

Response Posted - 08/02/2011 : 18:37:53

Don't have any, but will walk out and try one tonight. If it is no good I'll take one tomorrow after I get home from the "Y".

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frog0911
Master Marine Consultant

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USA
1349 Posts

Response Posted - 08/03/2011 : 13:01:29

The night pictures were not very good so here is today's. The pictures show the bungee I use now instead of the spring and the rest of the hookup. Found the bungee a HF cheap and I change them out about every six months or when they start to rust.

Edited by - on

John Russell
Master Marine Consultant

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USA
3444 Posts

Response Posted - 08/03/2011 : 13:41:52

A simple and elegant solution. Thanks!!!

Edited by - on

GaryB
Master Marine Consultant

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USA
4304 Posts

Response Posted - 08/04/2011 : 06:39:10

Definitely don't leave it in forward. That clicking sound you hear is the clutch dog and you will wear it out if you let it click like that.

I leave my Suzuki in neutral and have since I bought the boat almost 4 years ago. Haven't had any issues so far. If the winds are not too high I will sometimes leave it in gear as long as the propeller doesn't start rotating. I don't really notice much of a difference in drag between neutral and in gear and not rotating.

My boat is definitely faster if I raise the motor where the prop doesn't drag.

Fyi...from my days of flying multi-engine piston airplanes, the drag associated with a rotating propellor that's not producing power is equal to a solid plate the diameter of the propeller. That's why airplanes and some boats/ships have propellers that can be feathered. Feathering streamlines the individual blades and stops the rotation.

At the relatively low speeds we travel I doubt the drag is very significant.

Edited by - GaryB on 08/04/2011 06:57:43

redviking
Master Marine Consultant

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USA
1771 Posts

Response Posted - 08/04/2011 : 09:46:57

I'm voting for putting the engine in reverse. Drag does increase when in neutral and you've got spinning parts sitting in bearings. Why spin em any more than you have to?

sten

Edited by - on

Stinkpotter
Master Marine Consultant

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Djibouti
9081 Posts

Response Posted - 08/04/2011 : 21:19:14

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by GaryB
 ...the drag associated with a rotating propellor that's not producing power is equal to a solid plate the diameter of the propeller.
<hr height="1" noshade id="quote"></blockquote id="quote">There are some counter-intuitive things I can be convinced to believe... That's not one of them. My dad worked on electric pitch propeller problems on twin-engine B-26 bombers during WWII, and the effect you describe was happening when the engines were at full power (take-off) and one prop suddenly went to zero pitch so that the engine wound up to max RPMs... That was like a solid disk on one side with full power on the other, and the plane would instantly cart-wheel into the ground.

Stopped and fully feathered a prop obviously is almost like no prop. A pitched, spinning prop is somewhere in between--the force that makes it spin is the drag. I believe a locked prop might have (counter-intuitively) less drag than a spinning one when it's an inboard prop directly behind a keel. Otherwise, I'm unconvinced. My recollection was that when I locked my submerged outboard prop in reverse, it slowed the boat a little. When I let it spin, it made a hum. That was the trade-off we faced.

Edited by - Stinkpotter on 08/04/2011 21:21:22

John Russell
Master Marine Consultant

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USA
3444 Posts

Response Posted - 08/05/2011 : 06:04:14

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Stinkpotter When I let it spin, it made a hum. That was the trade-off we faced.
<hr height="1" noshade id="quote"></blockquote id="quote">It was the noise that actually started this whole thing. I wasn't enjoying the break in my serenity as I sailed along in a peaceful quiet with the exception of the D@^^ prop!

Gary, I suspected as much about the clicking sound. That's why I thought reverse would be the better option.

Edited by - on

GaryB
Master Marine Consultant

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USA
4304 Posts

Response Posted - 08/05/2011 : 06:17:03

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Stinkpotter
 <blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by GaryB
 ...the drag associated with a rotating propellor that's not producing power is equal to a solid plate the diameter of the propeller.
<hr height="1" noshade id="quote"></blockquote id="quote">
A pitched, spinning prop is somewhere in between--the force that makes it spin is the drag.
<hr height="1" noshade id="quote"></blockquote id="quote">
I was speaking in general.

I would agree with your statement above. The more pitch the propellor has above zero pitch the less drag induced up to the point it is feathered. I would think that the difference in the drag would not be that noticable until you start getting above 10 degrees of pitch.

Edited by - on

GaryB
Master Marine Consultant

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USA
4304 Posts

Response Posted - 08/07/2011 : 17:45:40

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Stinkpotter
 <blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by GaryB
 ...the drag associated with a rotating propellor that's not producing power is equal to a solid plate the diameter of the propeller.
<hr height="1" noshade id="quote"></blockquote id="quote">My dad worked on electric pitch propeller problems on twin-engine B-26 bombers during WWII, and the effect you describe was happening when the engines were at full power (take-off) and one prop suddenly went to zero pitch so that the engine wound up to max RPMs... That was like a solid disk on one side with full power on the other, and the plane would instantly cart-wheel into the ground.
<hr height="1" noshade id="quote"></blockquote id="quote">
Since we've already gotten OT I'll ask for forgiveness.

Or engine failure like this...
http://www.youtube.com/watch?v=13LPBImLcxo

and with sound...
http://www.youtube.com/watch?v=QvplU_5ysjk

The plane in this accident is actually a Douglas A/B-26 Invader not the Martin B-26 Maruader you're dad worked on.

What an idiot and waste of a good plane. He had plenty of runway to abort. Luckily, everyone walked away.

Edited by - GaryB on 08/07/2011 17:59:40

Voyager
Master Marine Consultant

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USA
5378 Posts

Response Posted - 08/07/2011 : 18:25:01

I agree with Gary B and Dave Bristle.

When sailing on Passage, I've always popped the engine up to the top level on the bracket and put the engine in neutral.

The engine hums when I hit 3.1 knots through the water and stops humming at 3.9 - that's how I gauge my speed.

It's worked that way since day 1. I do notice a slight drag, but nothing to write home about. And if I want to make time or speed, I will tilt up the engine and take the engine completely out of the water.

It doesn't seem to have any negative effect on the motor. I replace the gear oil every year and have never noticed any problems with the grease or the mechanism.

Edited by - on

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