Reverse rotating the outdrive

SuperNova

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I was looking at my control head the other day while I was replacing the control cables and I realized the shift cables could be mounted so as to reverse the action of the control(pull instead of push and vice versa) with the effect of when I put the control in forward, the oudrive will go into reverse. So I was thinking, if I wanted an easy way to counter rotate one of my props, all I really had to do was mount the cable the other way and install a left hand prop. The engine and the outdrive will still rotate the same way, the only thing that will change will be the gear I engage for forward or reverse will flip-flop and the direction of the prop shaft will change. Anybody see any reasons this wouldn't work? Thanks in advance.
--
Stan
 

Coors

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Re: Reverse rotating the outdrive

Don't put many rpms in reverse, as the drive is built to be used in forward?
 

Haut Medoc

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Re: Reverse rotating the outdrive


Mercs are not set up for that as far as I know....
It can be done with certain Volvo Pentas....
OMC? Dunno......:D
 

SuperNova

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Re: Reverse rotating the outdrive

As far as I know, the forward and reverse gears are identical, and everthing else will be spinning the same way it would normally.

What does N/M mean, Reelpoor?
 

Nova II 260

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Re: Reverse rotating the outdrive

I believe the ratios are different and was always under the impression not to run high RPM's in reverse, as mentioned by Coors. I'll check the manuals. If it were to work, what would you gain by this? Just curious.
I have a new Binacale mount control and need to install it, also. Did you have any problems? What is the cable lenght for our 26' Nova's? eMail me if you will.
Eric
 

Reel Poor

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Re: Reverse rotating the outdrive

What does N/M mean, Reelpoor?

It means "never mind.

I was going to say I know the Volvo Pentas will turn either direction. Not sure about the Mercruisers. I was thinking the Bravos might (because of their cone clutch) but there may be a problem in the lower gear case. Some counter rotating lower gear cases are designed different than standard rotation. I'm don't know if this is true for Bravos but I do know some outboard lower gearcases are different. Namely from my experiance Yamaha outboards.
 

Limited-Time

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Re: Reverse rotating the outdrive

I'm not sure but there could be issues with the thrust, bearing loads, and upper and lower gear loading. There has got to be a reason Merc makes a C/R unit.
 

SuperNova

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Re: Reverse rotating the outdrive

Well, I think I'm gonna give it a try, worst case scenario-I end up having to rebuild the outdrive, so what. I'll let you all know how it goes.
--
Stan
 

SuperNova

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Re: Reverse rotating the outdrive

Alpha 1 gen 1.

I am curious why Bond-o and Don are strangely silent on this one.
 

Reel Poor

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Re: Reverse rotating the outdrive

I think your asking for trouble. I was just lookin at the manual for the standard and counter rotating drives. The counter rotating drives has many more and different parts in the lower gearcase propeller shaft design. I don't think the drive is going to hold together at high rpms under a steady load. I believe your lighting a fuse on something thats gonna blow up.

Look HERE for counter rotating and HERE for standard rotation to compare parts.
 

shammesfah

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Re: Reverse rotating the outdrive

blow, blow, blow your drive gently to the shore
If you run in reverse you will row for sure

I guess by your post you have twin screw

Merc did not make a counter rotate drive so you did not have to go though the bother of changing your cable throws
If you want to change to a counter I have a new one cheap I sent you a private message
 

SuperNova

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Re: Reverse rotating the outdrive

I understand what you all are saying, but I'm still not a believer. I think I'm gonna have to learn the hard way. I looked at those fiches and I see the differences you are talking about, but I think they are inconsequential. I don't need a reverse rotation outdrive shammes, b/c I don't have a reverse rotation engine. I have two right hand engines and I just want to spin one prop counter-clockwise without changing to a complete left hand setup. I don't care about having to rebuild the outdrive if it does damage it. I've only done about a thousand rebuilds, so one more won't matter. Consider it a test, and I'll be the guinea pig. Oh, and shammes, what you said about using he other cable mount for the lefthand outdrive doesn't make any sense. If you put in a complete left rotate setup, you are still gonna push and pull the cable the same as for a right hand setup. Forward gear is still forward gear and reverse gear is still reverse gear, so you still have to pull the cable to engage reverse and push it to engage forward, same as right hand drive.
--
Stan

p.s. Don and Bondo still curiously silent, I figured the "experts" would weigh in on this for sure.
 

shammesfah

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Re: Reverse rotating the outdrive

Counter rotating mercruiser lower units are used on Standard rotating engines to end up with counter rotating prop (you do have to change the cable throws though) you do not need change the engine or want to run a standard rotate in reverse

I'v sold many of these units to people who like to (Learn the Hard Way)
If you learn from your mistakes your ahead of me
I still hit my thumb with the hammer

In short the (Counter rotation) of mercruiser is done in the lower unit

http://www.sterndrives.com/mercruisersterndrives.html A note about ROTATION
Do not confuse engine rotation with sterndrive or propeller rotation
ALL sterndrive Mercruiser Engines are left hand (standard, counterclockwise) rotation.
Most single engine boats use a right-hand rotation drive unit meaning that
the propeller rotation is right-hand (standard, clockwise) rotation.
Counter rotating drives are left-hand (counter, counterclockwise) propeller rotation.
Counter rotating drives have only been around in numbers for the last few years.
The advantage of having two drives rotating in opposite directions are
increased speed, improved slow and high speed handling, better course tracking,
more level ride, improved fuel economy and easier docking.

NOT ALL DRIVES CAN COUNTER ROTATE!
The drive must be specifically designed to be a counter rotation drive.
Attempting to run a standard rotation drive in a counter rotation direction
will positively destroy the drive in just a few minutes.

In most applications the RH (standard) drive is mounted on the starboard side.
The LH (counter rotation) drive is mounted on the port side.
The LH drive must have a LH propeller. The LH shift cable must be reversed at the binnacle to pull instead of push
for forward gear. Most controls allow for either direction by simply repositioning
the cable mounting location and attachment.)


(
 

SuperNova

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Re: Reverse rotating the outdrive

O.K. shammes, I get what you're saying now. That explanation was much clearer to me.
--
Stan
 

Haut Medoc

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Re: Reverse rotating the outdrive


Found out the hard way, didya?........:p
 

SuperNova

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Re: Reverse rotating the outdrive

Nope, not yet. I am still going to run the experiment. If I have to buy a new outdrive or rebuild I am prepared to pay the price. But I want to know for sure and I am the type that can only learn certain things by experience. Plus, I would want to speak knowledgeably about it in the future and the only way I could ever do that is by firsthand experience, or I may come up with a way it can be done. Heck, shammes makes a living selling reverse rotation outdrives, so why would he tell me what I want to do will work? I am cynical like that. No disrespect meant, but I really don't know him from Adam. But his explanation is now clearer to me. Doesn't mean I think he's right or wrong, just means I understand his argument.
--
Stan
 

shammesfah

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Re: Reverse rotating the outdrive

First You say my advice on cables "doesn't make any sense" , then you liken me to a car salesmen that won't tell you the truth. Where is the love
I'm going to hit myself in the groin to take away the emotional pain and humilation you put me through sniff sniff
 

SuperNova

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Re: Reverse rotating the outdrive

I'm sorry man! I still love ya! Now gimme that beer!!:D Seriously, don't be offended. I am just one of those idiots who has to try things sometimes and then when it does blow up, I just gotta take it apart and figure out why. Just so I know in advance- how much does one of the counter rotation outdrive go for. Oh, and on the positive note, you did educate me. I always thought Counter-rotation outdrives went hand-in-hand with counter rotation engines. The second option is also to just install a counter rotation lower unit instead of the whole outdrive if I read you right. The only difference is in the lower gearset and bearings around the prop shaft from what I gather from your posts. Course, seeing as to how it's getting a little more likely to blow something up, I just may have to convince my brother in law to be the guinea pig. Won't be difficult.
--
Stan
 
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