any issues running a counter rotating engine for a single engine use?

bcraigan said:
Any problems running a counter rotator for a single engine?
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I cannot think of any, other than the fact that your torque will be opposite the norm. The motor should have the proper torque trim tab attached to it, so the only thing you may have to do is set it up for your boat. A counter rotating prop will have wheel walk to the right.

Determine how much wheel-walk is occurring. Test drive the boat at full speed with the steering amidships (in the center). Observe how much the boat turns. Boats that turn opposite the prop rotation need more angle on the tab. Boats that turn the same direction as the prop rotation need less angle on the tab. Stop the boat to adjust the tab. Hold the trim tab firmly in position by hand and loosen the trim tab bolt. Rotate the tab in small increments in the appropriate direction, then firmly tighten the bolt. Test drive the boat again. Observe how the boat handles and make further adjustments as needed.

That should do it. Red skys at night...
 
The only drawback to running a lefty in a single app is that you're limited in prop selection. You will pretty much only have basic offshore style props available to you in a left hand rotation.
 
according to Mercury, their counter unit is stronger than the standard( I know its shimmed a lot closer tolerance), but I've seen more(% wise) counters blow up than standard lower units
 
My 92 Yammie is counter rotation. No issues with it other than the feeling of torque in a different direction.
 
same, just beveled backwards. i was also told some eariler models used the reverse gear in the forward position and this is why some had premature failure, reverse gear was not as "beefy".
 
as far as I know, they all(CR units) use the rear most gear as fwd gear rather than the front side gear as fwd(confusing isn't it). The counter units use flat torrington bearings to support the load rather than tapered bearings, OMC units didn't really change that much as they allready use teh torrington bearing. The flat bearing is supposed to be better than a tapered roller. I do know they are a pain to set up, and they have closer tolerances, I think incorrect set up may be the main cause of issues with them
 
i'd be more worried about what they came off of rather than it just being a counter, if it was the twin to a pair of offshore engines pushing a heavy offshore boat to the Georgetown Hole and back twice a week, something made them think to repower. Or if was a loose motor that ended up being rigged at a dealership( it happens more that you think) then its no big deal, just watch out for corrosion and check the play in the steering shaft, make sure your not gettings some one wore out motors off of their tournament boat.
 
Got a lead on a yamaha down in Hilton Head right now. It's at a dealer that had someone come in and repower. Also checking out a 140 evinrude in the upstate sometime too. I'm definitely learning patience in this process...lol
 
I've got a 140 I'm looking at. It supposedly came from upstate new york but is freshwater use... anyone from upstate ny? Is that a freshwater mainly use area?
 
bcraigan said:
I've got a 140 I'm looking at. It supposedly came from upstate new york but is freshwater use... anyone from upstate ny? Is that a freshwater mainly use area?
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Upstate NY "usually" means near the Finger Lakes Area or Lake Ontario. So yes, I would have to say that area is frestwater use. :head:
 
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