Does OMC use counter rotating engines or drives?

Spivy30

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I just bought a 1989 Fourwinns 315 Vista with Twin 5.7s but the outdrives had been stolen off of it. They were OMC Cobras. I am new to Cobras and only know what I have read about them recently. They do seem to be good drives along as they are maintained and adjusted properly. My question is...the previous owner still had the props and one was counter rotating which would mean the boat had a counter rotating powerpack...if I buy two standard rotation drives and put new props on the boat will it work or will one be backwards still because the engine is counter rotating?

If anyone has some must know info for cobra owners please tell me I dont want to wreck these once I put them on.

Thanks,

Andrew
 

Spivy30

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Re: Does OMC use counter rotating engines or drives?

I would like to retain the counter rotation but I cant find a drive for under $1500 where I can find two standards for $400-500.
 

Summer Fun

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Re: Does OMC use counter rotating engines or drives?

.if I buy two standard rotation drives and put new props on the boat will it work or will one be backwards still because the engine is counter rotating?
I have the same standard rotation outdrives and you'll fine

I run a 15x15 props and my tug can hit 51.9 MPH. :)

because the engine is counter rotating?
I doubt you have that with cobra's.
 

Gary H NC

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Re: Does OMC use counter rotating engines or drives?

I would like to retain the counter rotation but I cant find a drive for under $1500 where I can find two standards for $400-500.

Good Luck! 4 or 500 is not going to happen unless it is junk. Ebay is a gamble but that is about the only place.

NO WAY i would invest the money in a dual powered OMC setup....just my opinion...
 

superbenk

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Re: Does OMC use counter rotating engines or drives?

What about SEI conversion kits? I think if I was looking at replacing outdrives for a Cobra, that's the first place I'd look.

Might be more than the used stuff you're finding, but I sure would trust it a lot more & you'd get a warranty and a drive that's supported.
 

Don S

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Re: Does OMC use counter rotating engines or drives?

My question is...the previous owner still had the props and one was counter rotating which would mean the boat had a counter rotating powerpack...if I buy two standard rotation drives and put new props on the boat will it work or will one be backwards still because the engine is counter rotating?

Crank the engines over and see which way the crank turns. If, (while looking at the front of the engine) the pulley turns CLOCK WISE, that is a standard rotation engine. The counter rotating engine turns COUNTER clockwiswe.
If both turn the same way, the the reversing was done in the outdrive. I really don't recall if the Cobra drives had Counter rotation.

EDIT: Changed my directions to show the right direction of rotation..... I had them reversed :redface::redface:
 

Bondo

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Re: Does OMC use counter rotating engines or drives?

Crank the engines over and see which way the crank turns. If, (while looking at the front of the engine) the pulley turns COUNTER CLOCK WISE, that is a standard rotation engine. The counter rotating engine turns clockwiswe.

Ayuh,.... Boy O Boy,... I don't getta do This very often,.... :D :D

I Believe, you've got that, Exactly, Backwards,....... ;) :D

Engine Rotation is Always determined at the workin' end of the motor, in our case, the Flywheel...
While Standard rotation is in fact Counter-Clockwise,...
The pulleys on Bazillions of SBCs turn Clockwise.... The Standard rotation expected....

If the Pulleys are turnin' Counter-clockwise,... You've got a Counter-rotatin' motor..... :D :D
 

Spivy30

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Re: Does OMC use counter rotating engines or drives?

I have a friend who owns a marine parts place so they are solid drives for the price. SEI does make a conversion kit. I don't have a problem with cobra if theyre filled with gear lube the correct way and the shift cables are adjust properly they're better drives then alpha ones.
 

Don S

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Re: Does OMC use counter rotating engines or drives?

Ayuh,.... Boy O Boy,... I don't getta do This very often,.... :D :D

I Believe, you've got that, Exactly, Backwards,....... ;) :D

Ayuh..... Ya got that right, I screwed that up big time :redface: :redface:

I did go back and edit it.
 

Don S

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Re: Does OMC use counter rotating engines or drives?

What about SEI conversion kits? I think if I was looking at replacing outdrives for a Cobra, that's the first place I'd look.
.

The only thing about that option, is with twins, he is still looking at over 4 grand for two drives, two conversion kits, and a couple of props.

There really is no cheap way out when you go looking at a boat with 2 missing outdrives.
 

Bondo

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Re: Does OMC use counter rotating engines or drives?

Originally Posted by superbenk
What about SEI conversion kits? I think if I was looking at replacing outdrives for a Cobra, that's the first place I'd look.
The only thing about that option, is with twins, he is still looking at over 4 grand for two drives, two conversion kits, and a couple of props.

There really is no cheap way out when you go looking at a boat with 2 missing outdrives.

Ayuh,... I'm guessin' this is yet another Steal of a Deal, Except it's OMC powered....

'course the reality of it is, it's Cheap, Because it's OMC, without drives....

I suggest that Spivy30 bite the bullet, 'n Refit the whole thing to Volvo or Mercruiser,...
Selling off the OMC scraps might even pay for most of the refit...

What $uck$ wor$e i$ it'$ Twin$.....:rolleyes:
 

superbenk

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Re: Does OMC use counter rotating engines or drives?

The only thing about that option, is with twins, he is still looking at over 4 grand for two drives, two conversion kits, and a couple of props.

There really is no cheap way out when you go looking at a boat with 2 missing outdrives.

No doubt about no cheap way out unless the drives he's talking about really are solid & he doesn't mind maintaining them. If I had the cash, I'd be liking the idea of a current & supported drive setup like you get in the kits. Maybe it's just the bitterness of having a Stringer talking ;)
 

Lou C

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Re: Does OMC use counter rotating engines or drives?

The way the counter rotation was handled in the Cobra drives was that they used a counter rotating lower unit with a standard upper unit. So you'd need one standard drive, and a counter rotating one (with the special lower unit). Probably will be hard to find and the SEI conversion might be the best bet money wise (Volvo SX swap is a lot more money because of the cost of the drives) as long as you can get a counter rotating SEI drive...


http://www.dougrussell.com/partscat...6,688,687,689,690,691,692,693,694,695,696,697
 
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