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garbubba
01-28-2011, 08:49 PM
I'm still searching for a motor for my '87 cuddy. Want a carb yammie, but since I have merc controls I'd settle for a 150 merc. I've seen a few deals with a pair of counter rotating props & it got me thinking.

If you had only one engine, why would it matter which way the prop spins? It would just torque in the opposite direction, right?

And then why are counter rotating engine generally cheaper? & prop's too?

Doug

Destroyer
01-28-2011, 09:19 PM
I'm still searching for a motor for my '87 cuddy. Want a carb yammie, but since I have merc controls I'd settle for a 150 merc. I've seen a few deals with a pair of counter rotating props & it got me thinking.

If you had only one engine, why would it matter which way the prop spins? It would just torque in the opposite direction, right?

And then why are counter rotating engine generally cheaper? & prop's too?

Doug

Supply and demand basically. Not a lot of boats use twin engines, so when someone repowers or blows an engine the regular rotating engine sells easier than the counter rotating one.. so there are simply more used counter rotating engines available than the demand for them.. which equals a lower price as the owner trys to sell it.

Additionally, I think I recall reading that counter rotating engines are not as reliable as regular rotating engines? Now I could be wrong about that, so don't hold my feet to the fire over it... I just seem to recall reading about it somewhere....probably here. :head:

garagenc
01-28-2011, 09:33 PM
I have a opposite spin 200hp Merc on my V 20 and it has over 1,200 hrs on it and the only so far I've had to replace was a low pressure fuel pmp.

Bruce
01-28-2011, 11:58 PM
Additionally, I think I recall reading that counter rotating engines are not as reliable as regular rotating engines? Now I could be wrong about that, so don't hold my feet to the fire over it... I just seem to recall reading about it somewhere....probably here. :head:


no feet to fire here lol.. but please explain how that is even possible?? The only difference is reverse gears in the gearcase, you could make a counter rotator by simply changing the gearcase, so that means if you change the gearcase on reg rotation motor it now becomes less reliable?

I know you were just quoting, but I had to say something about it!! lol

Destroyer
01-29-2011, 01:20 AM
Do a search for counter rotating engine here, and go to this thread: any issues running a counter rotating engine for a single engine use? You'll see where I got my thoughts from.:head:

garbubba
01-29-2011, 08:01 AM
Thanks,

I'll go to that thread & look, but as has been stated it's just the foot that's different.

I've run many twins but on boats at work, I couldn't afford the boat, engines or fuel!

I was just thinking I could buy a pair, use one & sell the other & if the RH engine would bring more $$ why not use the LH engine?

Thanks,

Doug

Skools Out
01-29-2011, 09:20 PM
same motors just different foot i have a couple boats with twin currently but the counter unit is not as strong of a gear set but you can run one till the foot craps out then just buy a standard foot to replace it. the counter props are higher though.

Skools Out
01-29-2011, 09:22 PM
how ya like this set of matched twins on my wellcraft 250

http://i8.photobucket.com/albums/a46/Skools_Out/Wellcraft%20250/Picture068.jpg

http://i8.photobucket.com/albums/a46/Skools_Out/Wellcraft%20250/Picture080.jpg

http://i8.photobucket.com/albums/a46/Skools_Out/Wellcraft%20250/Picture070.jpg

Destroyer
01-30-2011, 01:01 PM
how ya like this set of matched twins on my wellcraft 250

http://i8.photobucket.com/albums/a46/Skools_Out/Wellcraft%20250/Picture068.jpg

http://i8.photobucket.com/albums/a46/Skools_Out/Wellcraft%20250/Picture080.jpg

http://i8.photobucket.com/albums/a46/Skools_Out/Wellcraft%20250/Picture070.jpg


LOL Skools, your skills never fail to amaze me. I saw these pics in the other post, but I'm thinking that paint would be a great idea. Make the blue one white or the white one blue... Given the colors of your boat, I'd go with the Johnson color scheme. But in all cases, that's an awesome setup. :clap:

Skools Out
01-30-2011, 08:42 PM
for right now i'm going to remove the cowlings and paint both the legs and foot on them white then put one set of Johnson the other Evinrude set boat till i decide to sell then it will get 2 johnson cowlings lol

scook
01-30-2011, 09:15 PM
Well, they are ugly, but I bet that thing scoots when push the handle forward:)

Bruce
01-30-2011, 09:17 PM
lmao... That boat must fly!!!



BTW... to the op You can interchange yamaha/merc controls.

Stinky_Hooker
02-04-2011, 11:33 AM
Skools, I cant say for certain (and dont wanna be able to) but Im pretty sure you must have a small penis. :zip:

scook
02-04-2011, 11:41 AM
I don't know - you'd have to have some fair sized gonads to go WOT with that rig:clap:

Road King Cole
02-04-2011, 12:54 PM
If you have a single prop in the northern hemisphire it should spin counter clockwise to reduce counterturbulance caused by the coriolis forces. That of course can be overcome by installing a simple disfossilator compensator on the hyperaquanation bracket.

rkc

Stinky_Hooker
02-04-2011, 01:43 PM
What he said ^^

garbubba
02-13-2011, 08:38 AM
If you have a single prop in the northern hemisphire it should spin counter clockwise to reduce counterturbulance caused by the coriolis forces. That of course can be overcome by installing a simple disfossilator compensator on the hyperaquanation bracket.

rkc

Of course, now I get it, it's all so simple now!

Destroyer
02-13-2011, 02:36 PM
If you have a single prop in the northern hemisphire it should spin counter clockwise to reduce counterturbulance caused by the coriolis forces. That of course can be overcome by installing a simple disfossilator compensator on the hyperaquanation bracket.

rkc

Allow me to return the compliment RKC.... "What Road King Cole said".....







And that is, of course if you're living in the Northern Hemisphire. If you are in the Southern hemisphire you have to turn the disfossilator compensator on the hyperaquanation bracket 180 degrees due to the earth's magnetic fields. It's the same principal as the water in the toilet swirling one way in the north and the opposite way in the south. :head:

BuilderFL
02-13-2011, 04:57 PM
What the heck, for all that, keep the dam thing simple and install an iperfornicator trobolis on the upper anobolitros.:beer: