A quick survey who trailers their boat with the motor in gear?

[Stinnett21]

A spinning prop also causes more drag. This is why long distance sail boaters lock there props when under sail. I think they have a special mechanism to do this. They can't put the motor in gear because the rush of water over the prop would turn the engine over. But...getting back to reality, I think some decent points have been raised above but I suspect a large percent of readers of this forum stand little to benefit from putting motors in gear. Correct me if I'm wrong but it's mainly only those motors trailered in down position that spin due to air rushing beneath the boat. In contrast I've never seen an I/O prop spinning due to the fact they are normally always raised.

 

[bigcity]

This thread makes me laugh.
Clearly you guys don't work with bearings, gears, shafts and seals.

 

[DaleH]

This thread makes me laugh.
Clearly you guys don't work with bearings, gears, shafts and seals.

Ha, well that reply clearly says absolutely NOTHING ... lol!

So as others have pointed out, their OB manual as written by the Engineers that designed the motor says to "place the motor in gear whilst trailering".

And you? What does your sage advice tell us? Please elucidate us and tell us how YOU are soooooo much smarter than any of us and them?

 

[Douglasdzaster]

I had a boat motor mechanic tell me years ago to place the boat in reverse to avoid the wind turning the prop and the entire drive shaft which puts additional wear on the bearings, gears and whatever.
The same thing goes for carrying bicycles without preventing the wheels from turning---additional wear.

Yours is the first to say reverse. All the others have said forward.

 

[Douglasdzaster]

This thread makes me laugh.
Clearly you guys don't work with bearings, gears, shafts and seals.

Please don’t stop there. Are you a technician? Let us know how to properly take care of our lower units. What say you about putting them in gear? And is it forward or reverse?
I had a mechanic working for me that would say stuff like that then not tell me the solution. He was in fact a great mechanic but his attitude kept him on my radar.

 

[Douglasdzaster]

A spinning prop also causes more drag. This is why long distance sail boaters lock there props when under sail. I think they have a special mechanism to do this. They can't put the motor in gear because the rush of water over the prop would turn the engine over. But...getting back to reality, I think some decent points have been raised above but I suspect a large percent of readers of this forum stand little to benefit from putting motors in gear. Correct me if I'm wrong but it's mainly only those motors trailered in down position that spin due to air rushing beneath the boat. In contrast I've never seen an I/O prop spinning due to the fact they are normally always raised.

Now I have to get my wife to fallow me and tell me if my prop is spinning or not.
Seriously though since I started this thread I been thinking about putting mark with a sharpie on the prop to the unit and check it after a couple of miles but it could move just from a bounce. Guess I’ll have to put a camera back there.

 

[bigcity]

Ha, well that reply clearly says absolutely NOTHING ... lol!

So as others have pointed out, their OB manual as written by the Engineers that designed the motor says to "place the motor in gear whilst trailering".

And you? What does your sage advice tell us? Please elucidate us and tell us how YOU are soooooo much smarter than any of us and them?

That's funny, glad to see someone still uses a thesaurus. But I meant no disrespect. You guys are a wealth of info here, and know way more than I probably ever will about boat stuff. But, motors/gears are in my wheelhouse.

However, since you asked. No, not an engineer. But it's my 30+ yrs as a millwright, having visited nearly 1000 factories/shops to work out driveline, vibration, lubrication, alignment, sealing, binding and a host of other problems. I've spent the last 20+ at a plant with over 4500(yeah really 4500)pieces of equipment that a team of us are responsible for. All power transmission systems operate on some pretty basic principles. From 8' herringbone gears that cruise along at 15-20rpm down to 40Krpm spindle motors with ceramic bearing. Same with seals.
Don't get me started about engineers. If not daily, I work with ME's, WE's, EE's, MET's and others a couple times a week. They can and will suggest some of the dumbest things imaginable. Nice people, but MANY are educated well beyond their practical intelligence.

So, the comment about the seal without water over heating due to the prop spinning from air pressure. I would bet you a month's pay that that's never going to happen. The working temps on seals today are between 250*f and 450*f. Neither of which you'll ever get close to with a spinning prop. The 2 temp concerns for seal failure(which cause hardening) are outside temp, underlip temp., where it actually touches the spinning shaft. The other big concern is garter failure, and then all bets are off. If a slow spinning prop could damage a seal, how would the hub seals ever make it to the lake?? Plus, even IF you could cool the seal with water. What about all the thru prop exhausts that are literally trying(and fail) to cook the thing.


Then the comments about cooling with gear lube/oil/... extra bearing wear from the spinning prop. That's not what goes on, how that works. That lower unit lube would be just fine at well over 150*. A temp it would never see without some sort of failure. In all my discussions about bearing failure, I don't ever recall bearing wear on lubricated, ZERO load bearings ever being considered. And that is what we're talking about here, zero load bearing wear. Surface hardening, yes. Bearing seal failure, yes. Wrong lubrication, yes. Lack of lube, yes.

As far as some manuals advising to put into gear I figure it's more CYA than anything else. Some dingdong probably tried to sue them because his lower unit went bad and Mercury never told him to trailer it in gear and that is what caused his problems.

Also someone mentioned a spinning prop on a sailboat creating more drag than a stopped 1. Got anywhere offhand that I can look at that??

So that's where I'm at.

 

[airshot]

That's funny, glad to see someone still uses a thesaurus. But I meant no disrespect. You guys are a wealth of info here, and know way more than I probably ever will about boat stuff. But, motors/gears are in my wheelhouse.

However, since you asked. No, not an engineer. But it's my 30+ yrs as a millwright, having visited nearly 1000 factories/shops to work out driveline, vibration, lubrication, alignment, sealing, binding and a host of other problems. I've spent the last 20+ at a plant with over 4500(yeah really 4500)pieces of equipment that a team of us are responsible for. All power transmission systems operate on some pretty basic principles. From 8' herringbone gears that cruise along at 15-20rpm down to 40Krpm spindle motors with ceramic bearing. Same with seals.
Don't get me started about engineers. If not daily, I work with ME's, WE's, EE's, MET's and others a couple times a week. They can and will suggest some of the dumbest things imaginable. Nice people, but MANY are educated well beyond their practical intelligence.

So, the comment about the seal without water over heating due to the prop spinning from air pressure. I would bet you a month's pay that that's never going to happen. The working temps on seals today are between 250*f and 450*f. Neither of which you'll ever get close to with a spinning prop. The 2 temp concerns for seal failure(which cause hardening) are outside temp, underlip temp., where it actually touches the spinning shaft. The other big concern is garter failure, and then all bets are off. If a slow spinning prop could damage a seal, how would the hub seals ever make it to the lake?? Plus, even IF you could cool the seal with water. What about all the thru prop exhausts that are literally trying(and fail) to cook the thing.


Then the comments about cooling with gear lube/oil/... extra bearing wear from the spinning prop. That's not what goes on, how that works. That lower unit lube would be just fine at well over 150*. A temp it would never see without some sort of failure. In all my discussions about bearing failure, I don't ever recall bearing wear on lubricated, ZERO load bearings ever being considered. And that is what we're talking about here, zero load bearing wear. Surface hardening, yes. Bearing seal failure, yes. Wrong lubrication, yes. Lack of lube, yes.

As far as some manuals advising to put into gear I figure it's more CYA than anything else. Some dingdong probably tried to sue them because his lower unit went bad and Mercury never told him to trailer it in gear and that is what caused his problems.

Also someone mentioned a spinning prop on a sailboat creating more drag than a stopped 1. Got anywhere offhand that I can look at that??

So that's where I'm at.

I have to agree somewhat, my son who was an experienced machinist was told by a 150k per year engineer with numerous pieces of fancy awards hanging on his wall and has written many engineering tutorials told my son the when he ran a standard tap all the way thru a piece of metal, he would end up with a left handed thread on the oposite side !! No kidding !!
He just assumed the guy was making a joke and made fun of his statement....long story short, the engineer was pissed and when my son proved the error of his statement, my son was fired !! I don't have enough fingers and toes to count the number of times " highly skilled" engineers have given out information that was untrue or based on theroy only. I have owned numerous boats in my 60 years of boating and had manuals for each one, never saw a recomendation for keeping it in gear for wear purposes !
To each his own, your boat, but I do believe there are other more serious areas to look at for wear concerns...

 

[airshot]

A spinning prop also causes more drag. This is why long distance sail boaters lock there props when under sail. I think they have a special mechanism to do this. They can't put the motor in gear because the rush of water over the prop would turn the engine over. But...getting back to reality, I think some decent points have been raised above but I suspect a large percent of readers of this forum stand little to benefit from putting motors in gear. Correct me if I'm wrong but it's mainly only those motors trailered in down position that spin due to air rushing beneath the boat. In contrast I've never seen an I/O prop spinning due to the fact they are normally always raised.

All of the sailboats I have been around use folding props that fold up to eliminate drag from the prop blades. Never saw a locked prop ! One day I was in the lake doing some experimenting with my small kicker motor. Testing to see how much drag the main engine might cause if left down or better off being tilted up. While in the down position I also checked allowing the prop to spin free (neutral) or putting the motor in gear, thus locking the prop. Gained between .2 and .4 mph according to my gps with the prop free spinning rather than locked. I would find it difficult to believe any speed gain from a locked prop, and every sailor I know is looking for ways to reduce drag !!

 

[InSaneFisherMan]

My manual says nothing about trailering with motor in/out of gear.

But it does state to avoid shifting gears when motor is not runing.

Just my opinion, but never been driving behind a trailering boat and seen the prop spinning fast enough that I thought it would cause any damage. Obviously, any movement cause wear, but so would trolling with OB motor in water.

Following your manual.

 

[Douglasdzaster]

That's funny, glad to see someone still uses a thesaurus. But I meant no disrespect. You guys are a wealth of info here, and know way more than I probably ever will about boat stuff. But, motors/gears are in my wheelhouse.

However, since you asked. No, not an engineer. But it's my 30+ yrs as a millwright, having visited nearly 1000 factories/shops to work out driveline, vibration, lubrication, alignment, sealing, binding and a host of other problems. I've spent the last 20+ at a plant with over 4500(yeah really 4500)pieces of equipment that a team of us are responsible for. All power transmission systems operate on some pretty basic principles. From 8' herringbone gears that cruise along at 15-20rpm down to 40Krpm spindle motors with ceramic bearing. Same with seals.
Don't get me started about engineers. If not daily, I work with ME's, WE's, EE's, MET's and others a couple times a week. They can and will suggest some of the dumbest things imaginable. Nice people, but MANY are educated well beyond their practical intelligence.

So, the comment about the seal without water over heating due to the prop spinning from air pressure. I would bet you a month's pay that that's never going to happen. The working temps on seals today are between 250*f and 450*f. Neither of which you'll ever get close to with a spinning prop. The 2 temp concerns for seal failure(which cause hardening) are outside temp, underlip temp., where it actually touches the spinning shaft. The other big concern is garter failure, and then all bets are off. If a slow spinning prop could damage a seal, how would the hub seals ever make it to the lake?? Plus, even IF you could cool the seal with water. What about all the thru prop exhausts that are literally trying(and fail) to cook the thing.


Then the comments about cooling with gear lube/oil/... extra bearing wear from the spinning prop. That's not what goes on, how that works. That lower unit lube would be just fine at well over 150*. A temp it would never see without some sort of failure. In all my discussions about bearing failure, I don't ever recall bearing wear on lubricated, ZERO load bearings ever being considered. And that is what we're talking about here, zero load bearing wear. Surface hardening, yes. Bearing seal failure, yes. Wrong lubrication, yes. Lack of lube, yes.

As far as some manuals advising to put into gear I figure it's more CYA than anything else. Some dingdong probably tried to sue them because his lower unit went bad and Mercury never told him to trailer it in gear and that is what caused his problems.

Also someone mentioned a spinning prop on a sailboat creating more drag than a stopped 1. Got anywhere offhand that I can look at that??

So that's where I'm at.

Cool, thanks for sharing your knowledge it’s appreciated.

 

[Douglasdzaster]

Wow I started this thread out of curiosity and to settle things with a discussion between my son and myself.
He’s probably forgot about it by now.
This has turned into a what type of oil should I use in my engine thread.
I’ve seen Ecoboost owners like myself get down right nasty as well as a small engine forum about oil.
I’ll be leaving my 1992 Yamaha in neutral since my maintenance manual as well says not to shift when outboard is not running.

 

[InSaneFisherMan]

Just for humor,

If it is an electric outboard, would the prop spinning, charge the battery?

 

[bigcity]

Just for humor,

If it is an electric outboard, would the prop spinning, charge the battery?

In theory yes, but according to this website it may take a minute to charge a battery! Running a Brushed DC Motor as a Generator. Circuits and definitely circuit analysis is WAY outta my depth

 

[bigcity]

Wow I started this thread out of curiosity and to settle things with a discussion between my son and myself.
He’s probably forgot about it by now.
This has turned into a what type of oil should I use in my engine thread.
I’ve seen Ecoboost owners like myself get down right nasty as well as a small engine forum about oil.
I’ll be leaving my 1992 Yamaha in neutral since my maintenance manual as well says not to shift when outboard is not running.

DUUUUDE, oil guys are/can be some whacked out fanatics! The stuff they study and break down is impressive. I'm on a couple oil BBS's from time to time and they are some anal MF'rs.

As a side note, I'm a big fan of Amsoil and have run it in my last 2 pickups totaling just shy of 600K miles. I think I'm going to try them on their claim of 25K miles between oil changes with their signature synthetic and filter. 2022 F250 with the 7.3l gas. I have test kits from Amsoil & Blackstone to get result of this oil change(10K) and will do it again after the 25K change.

 

[FuzzyGrub]

At camp, so reread the manual. The following is mentioned after an important/bold section about not relying on tilt/trim or tilt support while trailering.

It is in normal font and seems just to be informational.

“Shift the outboard to forward gear. This prevents the propeller from spinning freely.”

 

[sonny1]

I just wish we had a prop to worry about spinning or not.

 

[Zum]

It was pretty ugly when I first got it. But that was mostly carburetors. Changed the water pump first thing. Other than that no problem from the lower unit.

I kinda meant, the outboard is 30 yeats old, probably never trailered in gear ....and no damage to lower unit. Real life testing.

 

[Douglasdzaster]

DUUUUDE, oil guys are/can be some whacked out fanatics! The stuff they study and break down is impressive. I'm on a couple oil BBS's from time to time and they are some anal MF'rs.

As a side note, I'm a big fan of Amsoil and have run it in my last 2 pickups totaling just shy of 600K miles. I think I'm going to try them on their claim of 25K miles between oil changes with their signature synthetic and filter. 2022 F250 with the 7.3l gas. I have test kits from Amsoil & Blackstone to get result of this oil change(10K) and will do it again after the 25K change.

Man I send my samples to Blackstone as well from my F150 3.5 Ecoboost. I’m actually leaning towards a change to the new Pennzoil Platinum full synthetic. It’s made from natural gas. All other synthetics are made from crude and have more impurities. It’s also supposed to really stop LSPI which the Ecoboost is famous for causing fuel vapor to end up in the crank case. My little mule doesn’t like short trips, idling for long periods or anything under 2k rpms. It loves to be worked and pull a trailer. And every now and then I averaged 0-60 in 5.3 seconds.

Just for humor,

If it is an electric outboard, would the prop spinning, charge the battery?

 

[Douglasdzaster]

I kinda meant, the outboard is 30 yeats old, probably never trailered in gear ....and no damage to lower unit. Real life testing.

As did I. And I guarantee you’re correct. Everything I found told me the maintenance manual never got opened by some of the previous owners. And if something broke it got rigged up. When I checked the thermostat the bolt twisted.
You know what I’m not going to ramble this time. Y’all seen enough of that.