Origin of OMC Triumph 55

[mk30h]

Does any one know the history of the OMC 3-cylinder looper first released in 1968? This was the first motor that OMC built that I as a die-hard Merc kid thought was a great engine. Rumor that I heard was that it was the baby of Charlie Strang who left Mercury a few years earlier after Brunswick took control.
The engine sure had a Merc flavor to it from, the lower unit to it's sleek design. Far different from the other OMC's at the time which looked like they had been designed in behind the Iron Curtain. But that first 55 was a real head turner, especially with the short shaft.

I remember seeing a poster at the local mercury dealer explaining a lawsuit that Mercury had against OMC over 55. I think it had a triumph looking into a Mirror with a Merc 650 reflected.

It said. "Mirror, Mirror on the wall whose the fairest outboard of all"
The Mirror replied
"Johnrude, Johnrude starring at me looks like a mighty Merc to me".

So what's the real story?

[mk30h]

Evinrude info from 68

[Mark75H]

It does have that "new" look to it and I think you are right about it being Strang's baby. The only thing that it might have had in common with a Merc would be something in the lower unit, couldn't be the thru prop exhuast, that was originally an OMC thing way back. Merc's 3 cylinder 65 didn't come out until '72, well after the Triumph. Anyone have that poster hangin' around?

[Ray Neudecker]

Of all places, it is my understanding that the motor was actually the brain child of the old Scott Attwater Co and was bought from them in one of the many transactions involving their products.

[mk30h]

It's really amazing the motor still has modern lines 34 years after it was introduced. Nice engine, I was alway's envious of my friends whose family boat had this engine, even compared to the merc 50's and 650 4 banger. How did the Merc 650 3 cyl direct charge compare performance wise. I know the OMC had a bigger prop hub diameter and really had get up and go compared to the Merc. But maybe the Mercs were propped wrong, but I thought they were anemic in comparison. Don't know why Bombardier didn't keep building the 3 cly. Thought they were the best engines OMC ever made and Bomb missed an opportunity there. Best selling engine in north ont for years.

Never heard the McCollough story but they did exit the business around that time. That would be an interesting turn.

Ps Sam The merc 650 in the Mirror - Mirror poster was the 4 banger. Then again it mighthave been the 500

[Mark75H]

I have 7 Scott McCulloch triples and one OMC triple. The OMC triple bears no resemblence to them at all. (Other than being 3 cylinders.) They are pretty much 50's technology. In my research into outboard racing history I found and interviewed some of the Scott McCulloch engineers, there was practically no update work done there after the improvement to 75.2 hp in 1962. There are some rumors of 4 cylinder 84ci prototypes, but no actual technical improvements that could yeild anything resembling the OMC triple.

The McCulloch is a 63.2ci deflector piston type motor, regular diecast design. The Triumph is a 49ci loop charged design made by tricky lost foam casting technique.

There are also rumors that some Scott McCulloch designs went to Chrysler. The only truth to that is the fact that the racing development guys (Kies, Oxley and Snead) went to Chrysler when McCulloch decided to stop making outboards and Chrysler wanted to start racing. A few things were incorporated in the Chrysler racing lower unit that were proven in the McCulloch unit, but nothing in the powerhead except thin rings.

[Mark75H]

Anyone know the reasons McCulloch decided to quit making outboards? There were 3 . . .

[mk30h]

possible answer to three reasons

Chrysler(westbend), OMC, Merc?

or lawyers, lawyers, lawyers

[LakeRacer99]

These are neat little motors that turned this Merc gut on to these. I have a few early and late 70's 3cyl OMC and they remind me more of my V6 Merc than my inline Mercs.
Does anyone know how they squeezed 20more horses out of the thing later on? I have looked in the product brochures from early 80'(75hp) back to 1973 (65hp) and they have always been the same cid, bore and stroke.
Would that leave porting and carbs or compression? Love the short shaft.

[omc-v4]

ok 55 to 60 the 60 had another intake port added. the 65 had tuned exhaust the 70 has flat top pistons and differnt head the 75 is same as 70 except for 45 degree ramp at top of ex port. the hi po head did not come on them. for racers that use good gas.

[LakeRacer99]

"70 has flat top pistons"

Don't they all have the flat tops, I am pretty sure one of my 65s does. Please clarify for me.
Thanks.

[Mark75H]

#1 McCulloch was out done by OMC and Merc's higher hp motors. Once McCulloch wasn't right up there hp-wise with OMC and Merc, sales started falling. The highest hp McCulloch was the 75.2. Buyers go to the showroom where they can drool on the latest mega motor, even if they are only planning on buying a rowboat motor.

#2 The tooling was spent, used up, worn out; whatever you want to call it. More motors, even the old design clunkers could not be produced without a significant investment in new tools.

#3 Bob McCullouch had another investment that was paying huge dividends and did not require the massive reinvestment and management that the outboard business would have required of him. A real estate devlopment at the old US Army Air Corps R&R Site 6 in Arizona desert. Why work when you can just cruise? Better yet, why stick your neck out when you already own a sure thing?

Who knows what this location is called now?

[Backfire]

Gotta be Lake Havasu City, home of the "London Bridge".
Backfire

[Mark75H]

Correct. The race there was to attract attention to the development. This was not lost on the folks at Salton City. The real estate developers were the main sponsors at both locations.

[omc-v4]

70 & 75 have flat top pistons. You can put flat top pistons in any of them. Both have there on head.