Non counter rotating outboards, what can I expect? - The Hull Truth

RussH · 07-21-2008, 06:48 PM

I'm considering repowering my Scarab Sport w/ either Yamaha or Mercury Optimax 225 or 250 outboards. Currently I have twin 225 Evinrude counter-rotating outboards. Now I can dock and maneuver easily using just the engines to steer. The boat does not pull one way or another when running, it goes straight as an arrow. I have SeaNautics hydraulic steering w/ cylinders on each engine.

If I can get a good deal on two outboards that are not counter-rotating what problems, if any, can I expect? I've heard of boats actually running low on one side, not tracking straight while running, and getting a lot of prop cavitation with non-counter rotating engines. How about maneuvering the boat to dock and motoring around the channel, will steering with the engines change with non-counter rotating engines?

As a secondary question if I buy two outboards that weren't originally paired together and maybe not the same year but look identical with close to the same hours, what if any problems can I possibly come across?

Thanks, Russ

ABoater · 07-21-2008, 06:49 PM

Sounds like you already know the scoop on non-counter rotating motors.

Add a huge hit to the resale value of the rig when it comes time to sell...

Good luck!

solo464646 · 07-21-2008, 07:14 PM

i wouldnt do it unless it is like buy one get one free.. with 115s ok .. with 225s nope..

wetneck · 07-21-2008, 07:59 PM

if you get a great deal, find a good left lower unit.

rkatz · 07-21-2008, 08:18 PM

I am no expert, but here's my experience:
I had CR 130's and just switched to standard rotation 150's. With hydraulic stearing, the difference isn't all that terrible. However, turning left while running at speed is quite a bit harder than turning right. The tight maneuvering also suffered a little bit, but I am still getting used to it. As I get more used to it, it is getting easier to maneuver tightly using just the engines, but CR was noticeably better.

Not sure if this is just me, or if it's normal, but I also seem to have a difference in reverse, where I don't seem to get quite the same bite on the props. But again, that could just be me.

1NO REGRETS · 07-21-2008, 08:26 PM

Not worth doing, short run or long run.Buy one get one free, then buy a lower unit.Counter rotating will matter at the worst time.Sea keeping in rough water ,trimming ,the list goes on.the boat will lean at speed due to the prop bite.

potty dock · 07-21-2008, 08:31 PM

Quote:

1NO REGRETS - 7/21/2008 10:26 PM

Not worth doing, short run or long run.Buy one get one free, then buy a lower unit.Counter rotating will matter at the worst time.Sea keeping in rough water ,trimming ,the list goes on.the boat will lean at speed due to the prop bite.

100%

ScarabChris · 07-21-2008, 09:29 PM

if the deal is really good go for it and try it out, you could always just buy a good used counter lower unit later.

On the subject of mix matching engines.....as long as they are the same make, model and HP and close in age it won't matter if they weren't paired from the start.

rkatz · 07-21-2008, 09:43 PM

Quote:

1NO REGRETS - 7/21/2008 10:26 PM

Not worth doing, short run or long run.Buy one get one free, then buy a lower unit.Counter rotating will matter at the worst time.Sea keeping in rough water ,trimming ,the list goes on.the boat will lean at speed due to the prop bite.

My boat does 50 MPH now, and I have yet to notice any lean at all. What's even better, is that I don't have any "lien" either. That is, I got such a deal on my two brand new engines, that I didn't have to finance them.

Seriously, I tend to agree with Scarab Chris, and that was my ultimate decision too. My deal was so good that I figured I could switch to counter rotating down the road, if need be. So far, it hasn't bothered me enough to switch.

Mr. Demeanor · 07-21-2008, 09:45 PM

You could sell your new lower unit and probably buy a used CR. See wha they are gong for vs. buy a CR motor new.

On Bravo I/O drives you can switch the cables to run on drive in reverse and switc to a CR prop without any ill effects. Is there a reason you cant do this with an outbaord?

ScarabChris · 07-22-2008, 11:10 AM

Quote:

Mr. Demeanor - 7/21/2008 11:45 PM
On Bravo I/O drives you can switch the cables to run on drive in reverse and switc to a CR prop without any ill effects. Is there a reason you cant do this with an outbaord?

It depends on the throttle binnical, I know on the older OMC controls you can swap the cable so it throws the cable in the opposite direction. The new BRP controls don't allow that. Then the question is weather the lower unit can handle a heavy load in the reverse gear. I don't think so but i could be wrong.

I know it to be true what Demeanor is saying. My buddy has a 30 Scarab with twin small block Mercs and to test the props running inward he swaped the props and just put the shift levers in reverse to go forward and it worked fine.

second time · 07-22-2008, 04:57 PM

We had a 2005 31 contender with twin Zuki 250 both standard rotation. Only real complaint was slight cavitation of one of the engines at high speed cruise. Slight trim adjustment and the problem goes away, I would do it again except for the possible negative feedback at resale.

RussH · 07-24-2008, 02:11 PM

I've been out of town for a while so sorry for taking so long to respond.

As far as resale goes I really don't care because once I repower I will probably keep the boat until if falls apart. Trying to sell a boat with a pair of carbed thirsty 2 strokes is almost impossible unless gas drops significantly. I love the boat but right now I'm having a hard time justifying the cost of running it.

A guide we fish with has two Merc Opti's 225HP but they are 2 years apart in age (2003 & 2005) and both standard rotation because his boat is a single engine he has no use for a counter rotating engine. The engines have about 1,500 hours on them but he said he would personally warrant them for 1 year because he has never had a single issue with them. He only wants $8K for the pair.

Taking out the hit in resale value and based on the responses so far I think it may not be that bad of a problem to deal with. I can use my trim tabs to counter any lean but if I can't manuever the boat like I can with my counter rotating engines, that would be a deal breaker and I won't even consider it.

Thanks for the responses.

Russ

RussH · 07-24-2008, 03:21 PM

Can anyone confirm that a 2003 & 2005 are identical? Are all the parts the same and interchangeable?

Getting a replacement lower unit is a great idea. I was under the assumption that there were other differences besides the lower unit gearing.

What cost can I expect to re-power from Evinrudes to Mercury? I thought about $1,500 in labor to swap them out including the controls and guages, is this in the ballpark?

Any guess of how much more efficient these Opti's would be compared to my 1990 Evinrude 225's?

Thanks, Russ