Johnson/Evinrude 3 cylinder 55 and 75 questions

[john rowley]

I have some questions about the 3 cylinder omc engines from the late 60s and 70s. I have a 1975 75 hp Johnson Stinger 2 with the long 20" foot. Does this motor have the high compression head and big bore carburetors? Also, what does Stinger2 mean...what is the deal with the 2? This motor is the one with the giant "75" written on the hood and the motor is all orange.
I also have a short shaft 15" (nitro gearcse) Evinrude 75 hp. It is painted dark blue except for the foot which is silver. Did they come this color or was it repainted? What year model motor could this be? Also, would this motor have the high compression head and big bore carburetors? I was told this motor was an equivalent of a Johnson Stinger...Is that true?

What about a 55 hp Evinrude 3 cylider shortshaft (15") motor. I want to take the 15" mid and foot off the 55 hp Evinrude and put it on the orange 1975 75 hp Johnson Stinger 2. Will this work? What is the difference between the 55 hp Evinrude and the 75 hp Johnson Stinger2 besides horsepower?
Last of all, what exactly is a Johnson Stinger? Is it a high performance model of the regular 3 cylinder omcs or is it just a name? If there are differences, what are they?
Also, how do you tell if the motars have high compression heads and the big bore carburetors? Do all Stingers have the high compression heads and the big bore carbs?
Where can I get big bore carbs and high compression heads? Who is good at modifying these engines as a service?

Thanks for any and all input!

[Mark75H]

Ed Runne in PA does the best modification to these motors

Yes, the 75 Evinrude short is the equivalent of the Johnson Stinger2

The 2 designation was used because the plain "Stinger" designation was used on a V-4 Johnson race motor.

You can swap the powerheads

The differences are in the carbs, heads, pistons and porting

[Mark Poole ModVP]

Basically the same engines with many little changes along the way. The '68-'69 55 had pistons with a slight dome. As the engine progressed to the 65 hp version the ignition, carbs and heads changed. The pistons went flat top. From '75 to '76 the rods changed from narrow beam to wide beam. (Most racers used the narrow ones because they were considerably lighter.) There were many jet size changes and carb bore changes during the late '70's early '80's. The "big bore" carbs showed up around '81-82' and again, there were several types, some with mid range jets some without. The 20" shaft version in the 70's had a large blunt style gearcase. The 1972 65 hp flywheeel can be used on later versions and is a lighter flywheel again, preferred by hot rodders.

The engine that I raced was a 1976 powerhead, 1972 flywheel, head cut .080, 1985 carbs, 1970 something mid section and a 1983 nitro gearcase. All bolted up and was interchangeable.

In 1986 the powerhead was changed to a different 56 cu. in. block. In the end, the 49 cu. in. engine turned out to be more durable and smoother running.

[Mark75H]

Just yesterday on Hydroracer.net I saw someone making billet high compression full hemi heads with improved squish band for these motors.

The guy doesn't have the best reputation and the heads probably won't make as much difference as Ed's work does

[CALVIN]

Why does the 49 inch motor run better tah the 56 incher?

[Mark Poole ModVP]

I was a young but well experienced OMC tech back then and I don't think I ever saw a 56 ci motor idle as smooth as the 49's. The 56 motor also had a habit of lunching cylinder and pistons for no particular reason. Could have had something to do with the lost foam blocks. Some of OMC's lost foam parts were pretty rough. Knowing OMC they probably increased the displacement without doing any research on the dynamics of the crank and rods with larger pistons.

[john rowley]

How do you get in touch with Ed Runne in Pennsylvania?

[97mirage]

Someone asked this question on "Hydroracer" and there was a reply indicating the following contact number for Ed: 610 285 6807.

I don't know if it's current and never met this man, but have heard he is THE MAN. Let us know if this number works out for you. Good luck.

[JWTjr.]

Ed is excellent and does very good work. He knows his OMCs and especially the 3-cyl. engines well.

You will not find a better Evinrude/Johnson guy.

John

[ROLF]

Anybody have a current phone number for Ed the above number rings but never an answer.
Rolf

[MODIFIEDOUTBOARD]

07-26-2009 12:17 PM #4 Mark75H

Just yesterday on Hydroracer.net I saw someone making billet high compression full hemi heads with improved squish band for these motors.

The guy doesn't have the best reputation and the heads probably won't make as much difference as Ed's work does

SPAM!

07-25-2009, 08:21 PM
http://www.hydroracer.net/forums/showthread.php?t=16570
The head is NOT for a OMC 49 ci. I have NEVER made a head for “one of those motors” yet.

Back in 2000 when I was ready to buy a engine for modifiedoutboard hydro class racing there
wasn’t a Engine builder out there who could quote $$$ or HP or RPMs?????
Had to design and build my own Engine. 45ss w/(chamber out the mid-section). Limited # of Races but we did easily Pass National Champ with one of Ed’s 3cyl engines on more than one occasion.

Angry Customer:
Did have ONE angry customer in the past. Had to get a Third Party to Negotiate a settlement which was agreed to by the Angry Customer and met by myself. Payment was made.

Dishonest Buyer:
Sold a Old used gearcase to a person, after shipping only received a partial payment.
The Person was not satisfied with the condition of the gearcase so we BOTH agreed to a reduced price.
Did not receive payment and Person would not answer phone.
Had to get a third party involved to get payment from the Person.


Ed is the very best at what he does just was never able to get a hold of him!

[ML1]

Hi
Just bought a family boat from 1992 with a Johnson 60 3 cylinder with less than 50 hours on it !. There where also the 70 hp version of the same block. What is the differsnce ? Is it an easy thing to upgrade my 60 hp to a 70 hp, by this I mean sort of bolt on or bolt away some sort of restriction somewhere ?

[Fast Fred]

carb bore size and jets, it's a good idea to clean the glue line out of the ports on the fome molded case.

[regrp]

Does anyone have a current number for EdRunne , I'm building a pair of 1975 75hp Stinger 2 and need some input , parts etc.
Thanks
Reg

[DavisClarke]

Back in 2000 when I was ready to buy a engine for modifiedoutboard hydro class racing there
wasn’t a Engine builder out there who could quote $$$ or HP or RPMs?????
Had to design and build my own Engine. 45ss w/(chamber out the mid-section).