what are the best production 3 cyl engines

[Stevel77]

Speaking of evinrude 3 cyl engines are 86 ci engines superior? And what are the best years

[Da Bull]

My fav is the 49.9ci 75hp OMC. They came in 15 or 20inch and were right at home on the back of fishing boats, Houseboats or EP race boats. Being loop charged they lent themselves to modifications and loved methanol and nitrous.

[FMP]

The omc is solid , these run pretty good too.
https://www.screamandfly.com/attachment.php?attachmentid=468314&d=1456428113

[Stevel77]

We got 40 acres of outboards what years were 49 ci and the bigger 56ci we have quite a few

[Capt.Insane-o]

Yamaha hands down

[powerabout]

We got 40 acres of outboards what years were 49 ci and the bigger 56ci we have quite a few
once the omc 49 got mag cd then they are the same right though.
They can be seriously modified to make over 100hp as were the factory production race engines ( used longer rods from a 40 twin)
56 had some block design cooling issues early on but fixed in later blocks, can also be modded to 100hp but top end limited due to cast in exhaust

top of the pile was for F3 tunnel boats 31M 49ci engine ( custom block) was 8500+ rpm 120hp, not many in the USA.

[Stevel77]

Great info guys im actually trying to de is on one for this 14' tunnelhull we are building

[Capt.Insane-o]

Cheap way is a 49 15 inch nitro case and maybe Dewald can build you a propeller. Or more spendy find sst60

[Stevel77]

I find you don't see many for sale. So what year of motors have 49 ci

[sharpeye Mike]

They made the 49-75 HP with the nitro gear case from 1975 to 1988

I have the last year made in a Johnson called the Formula E and the Evinrude Sprint.
And they are not for sale in case someone ask lol

[Stevel77]

Lol I've been going through sheds full of outboards for days lol . Thanks for the info we got lots of 70s stuff! Just curious you never mention the 86 was it a garbage engine

[LakeFever]

Aren’t the 75 stingers 3 holes? I remember a fast one in the 80’s

[powerabout]

Lol I've been going through sheds full of outboards for days lol . Thanks for the info we got lots of 70s stuff! Just curious you never mention the 86 was it a garbage engine
86 was the first 70hp 56ci BUT never sold as a 15" ( except as sst60) and the 75hp 49 was also still in production
the 56 is fine, there are a couple of simple mods in service bulletins re cooling that some suffered
86 block was also used in the sst60 so it does work

[Capt.Insane-o]

The omc is solid , these run pretty good too.
https://www.screamandfly.com/attachment.php?attachmentid=468314&d=1456428113

Christ on a bike I am going to buy you a Force dildo for Christmas

[FMP]

As long as you have fun then

Odd thing to say

[Tomanytoys]

Christ on a bike I am going to buy you a Force dildo for Christmas

....you just made scotch come out my nose......

[Capt.Insane-o]

Those motors are obsolete, gearcases, ignition, mid section and trim suck balls, absoloutley zero prop selection and they are heavy. But whatever.

[FMP]

Not much truthful in that

[Capt.Insane-o]

Moral of the story, stick to the OMC or Yammers.

[Tomanytoys]

Moral of the story, stick to the OMC or Yammers.

....or a combination thereof....
Yamaha clamp / swivel with internal trim, 15” OMC can, Nitro case and SST 60 powerhead makes a nice package.

[Stevel77]

....or a combination thereof....
Yamaha clamp / swivel with internal trim, 15” OMC can, Nitro case and SST 60 powerhead makes a nice package.

Was thinking of doing these mods to a 86 70 johnson.

[sharpeye Mike]

86, 87 and some 88s have the right spline to mate to the nitro shaft.
All you'll need is the base plate of the 56s. It will bolt up nicely except for drilling out the mid, one size bigger to except the power head bolts

[Markus]

Moral of the story, stick to the OMC or Yammers.

3 cyl 90 hp Tohatsu is very nice, too.<object id="__symantecPKIClientMessenger" data-supports-flavor-configuration="true" data-extension-version="1.0.1" style="display: none;"></object>__PRESENT

[Mark Poole ModVP]

49 cu. in. is hard to beat. Well designed, durable. Enlarge and square the ports and shave head to get 190 to 200 compression. Big boost without issues.

[powerabout]

3 cyl 90 hp Tohatsu is very nice, too.<object id="__symantecPKIClientMessenger" data-supports-flavor-configuration="true" data-extension-version="1.0.1" style="display: none;"></object>__PRESENT
pressed crank or cracked rods?

[Chaz]

You guys sure Yamaha didn't make a bad-azz lil 15" mid … I could have sworn I seen one the other day .. :smiletest:


Power / Markus , The Japanese are a very traditional people .. call them by their full name .. :D


(トーハツ株式会社, Tōhatsu Kabushiki-gaisha)+OMC-BRP



No wonder you like them .. they built trains ( like BRP) and half the BRP outboards for the last decade .. and set up shop with them more than thirty years ago .. :p ;) :)

Chaz = thinkin, I would mention Force .. :iagree: But I don't want to get a FuPM present in the mail ... :nonod: :nonod: :nonod: :leaving: :cheers:<strike>
</strike>

[Markus]

pressed crank or cracked rods?

Don't know, never been inside one, all I know is that the offshore racers liked it almost as well as the 90 hp Yamaha.

It does have 3 piston rings:

https://yumbo-jp.com/en/catalog/outboard/tohatsu/tohatsu-1996/M90A-00221031-2/31-PISTON+%26+CRANK+SHAFT.html
<object id="__symantecPKIClientMessenger" data-supports-flavor-configuration="true" data-extension-version="1.0.1" style="display: none;"></object>__PRESENT

[powerabout]

You guys sure Yamaha didn't make a bad-azz lil 15" mid … I could have sworn I seen one the other day .. :smiletest:


Power / Markus , The Japanese are a very traditional people .. call them by their full name .. :D


(トーハツ株式会社, Tōhatsu Kabushiki-gaisha)+OMC-BRP



No wonder you like them .. they built trains ( like BRP) and half the BRP outboards for the last decade .. and set up shop with them more than thirty years ago .. :p ;) :)

Chaz = thinkin, I would mention Force .. :iagree: But I don't want to get a FuPM present in the mail ... :nonod: :nonod: :nonod: :leaving: :cheers:<strike>
</strike>



Yam 70 CES used in the T850 class
( for sure they copied the OMC 75, 15" small gearbox, tall gears)

[gotboostedvr6]

I had a Suzuki 65hp 15" that was pretty strong.

[JrCRXHF]

I kinda like the omc triple the parts are cheap they seem to run really well. I have 2 49's and 1 56ci in the garage right now.

[Chaz]

Yam 70 CES used in the T850 class
( for sure they copied the OMC 75, 15" small gearbox, tall gears)

Of course they did. All they had to do was ride their Tohatsu puppy across the street to their export shop …. (トーハツ株式会社, Tōhatsu Kabushiki-gaisha)+OMC-BRP

and copy their own design … :iagree:

[powerabout]

Of course they did. All they had to do was ride their Tohatsu puppy across the street to their export shop …. (トーハツ株式会社, Tōhatsu Kabushiki-gaisha)+OMC-BRP

and copy their own design … :iagree:

good question, what did the Tohatsu line up look like in the 60's

[Capt.Insane-o]

Tohastury

They are solid motors in that range.

[Chaz]

good question, what did the Tohatsu line up look like in the 60's

A lot like a early Hodaka … :D

https://octanepress.com/sites/default/files/styles/slide_big/public/1-0new_0.jpg?itok=doLqCPVK

Tuhatsu

http://i270.photobucket.com/albums/jj109/fbuis/motorcycle/tohatsu-museum1s.jpg

Or maybe a Bridgestone … ;)

https://i0.wp.com/www.bike-urious.com/wp-content/uploads/Bridgestone-Sport-50-Right-Side.jpg

Which morphed into the Yamatsu line-up we have today … :rolleyes:

https://www.kaygeeinflatableboats.com/wp-content/uploads/2018/06/MFS-40-F-2014_1024x1024.jpg

https://global.yamaha-motor.com/business/outboards/products/4st/v6-300-225/img/spec/img_001.jpg

[Stevel77]

Sorry to keep this post going but so from what I hear the 86 to 88 are the better ones but I was given a 93 60hp tracker model so im guessing this is a non bridgeport but were the 93 models any good? Is it worth kicking around this dead horse

[Scream And Fly]

I always thought that the OMC 3-cyl series of engines were a masterpiece of design. They have a lot of power and are extremely reliable.

[sharpeye Mike]

I'm pretty strong on saying that your 93 is a bridge port. the oval port came out in 94 and the carbs are made of plastic and aluminum. The oval port is a good motor too.
The 15" short shaft model is what you really want if you want to go fast. They are the only ones that came out with the nitro gear case.