We are very interested in your history with OMC Richard. It's a treat to hear about some of the inside stories. Anything you add at all about those days is more than we ever knew before. I hope you will keep more of your remembrances coming our way.
We are very interested in your history with OMC Richard. It's a treat to hear about some of the inside stories. Anything you add at all about those days is more than we ever knew before. I hope you will keep more of your remembrances coming our way.
I don't believe so, the 600 JLO and the Rotax 377 (one year only for Ski Doo in 1967) where both three port engines. I believe OMC chose this because of its there long history with two cylinder opposed engines. Both Evinrude and Johnson built many of them and called them outboards. The original snowmobile engine was designed by OMC Canada was a 362 CC rated at 12 HP. This engine was used on the 1965 E & J sleds, (they also built some under the OMC name) in '66 & '67 they were rated at 14 HP. In late '66 or '67 they moved to Milwaukee. 1968 the power was increased to 16 and stayed there in '69, its last year. The 437, introduced in 1969, was similar, but was a new engine.
The blitz kit was sold in 1970 only, in hopes of wining some races. The kit consisted of Back ported cylinders with 95 degree exhaust ports and a set of 8:1 pistons. Also included in the kit was a set of megaphones, .140 reed stops, a 125 HP outboard carb, and points were to be set at .022. This combination would pull 40 to 42 hp @ 6500 RPM. In 1971 I had a '71 Johnson Rampage with this kit, except I used the stock tuned mufflers. The comb was good for 44 hp @ 7000 RPM, I also had stuffer blocks on the crankshaft and a exp. drive. A stock Rampage (32 hp) would run in the low 60's, mine top out at 74. Ran it for 2 years, then the engine blew, a stuffer block came loose at 5500 RPM.
more to follow.
70ish is what we ran with ours as well. Showed many Arctic Cat El Tigres how things are done on the frozen Fox river. Always wanted to install the Wankel motor in a 15" track, loived it's smooth flow of power.
Anyhow, thank you for the stories, brings back lots of good memories.
Bill Schwab
Dirty Deck Brewing
Company
I seen an omc oppossed powered old golf car not long ago i think it was 14 hp.
I don't remember the brand cart , probably a Harley though he he.
Good info.
I believe Cushman was spun of in the 80's, Cushman built 2 different engines while I was at OMC and they were both 4 strokes. One was a single cylinder rated at 9 hp and the other was an opposed twin rated at 18hp and was used in the three wheel scooter. The differentials were built at the Evinrude assembly plant next to the outboard motors. Which brings us to the Cushman ATV (track style), this one used a 437 cc snowmobile engine. The 69' and 70' 437 had chrome bores and the later ones had cast iron bores. The change was for cost reasons only, cast iron bores are cheaper. I believe that the Cushman ATV were built in 71' and 72' and they were the ones that still used the chrome bore cylinders. The cast iron ones would not live in that environment.
Now some more comments of interest. When I started with OMC in Jan 1968,
It was the first year of the three cylinder 55, and don't get me wrong it was a sweetheart of an engine. I have a lot of respect for the 55 and all its siblings, but I don't have much respect for advertising. I don't know how many of you remember the the Doctor and his Wife (I am again indebted to my memory or lack of) who drove a boat with two 55 Triumphs from the head waters of the Missouri to the Mississippi with out bit of trouble. Now what I heard was, three power heads, as many gear cases and a possible Divorce.
More to follow.
More information, but I need to go back to late Sept of '68. I was working on the second shift to keep an eye on several accelerated engine endurance tests. The reason being we had just introduced the 437 cc (25 hp) in our '69 sleds and were doing some additional CYA. So one evening I was out on the outboard motor test floor killing some time, and they had just put a new 115 hp outboard in the test tank to run for the first time. Now the production Super. was use to seeing the 65 - 100 hp V-4s being tested which took between 2 - 2.5 sec, to accelerate from idle to test speed. He is know looking at a much smaller and nicer looking engine and the tester hits the gas. That 115 hits rated speed in one third the time, and the Super is out of the booth even faster. (with I think), a urge to ****. After seeing this I made up my mind to trade my 1967 Glastron 143V and Merc. 650 in. Enter Edgar Rose he tells Bill Speath (Chief Engineer) snowmobile engine division. Marine Engineering has three years to bring new products out, Snowmobile Engineering has 18 months. I must say that Marine Engineering did a great job updating the V-4's, they had three years, we didn't.
In the summer of '72 we were told to start on a series of three new Alternate firing twins. A 440, 440 and 650 cc engines with a target of 35, 40 and 50 hp.
More to come
That explains all the loose cylinder heads
, blown gaskets, and scoring on the JX-650's I remember the promo with Billy Kidd, 1964 Olympic ski champion driving through the snow to the sounds of the song from Deliverance...Fastest sled for the year it was released, then the wurlwind of problems....
Bill Schwab
Dirty Deck Brewing
Company
After four days of eating turkey, drinking bottles of wine and seeing far to many of my outlaws, I'm back.
I received the first crankcase and crankshaft for a 440 and put it together. Guess what, it would not turn, we soon found out the labyrinth seal between the two cylinders was too tight. After dealing with that, I fully assembled the rest of the engine. Let me back track a little here, the 437 opposed in it latest form would produce 27 + hp @ 6000 rpm open exhaust. The new 436 engine pulled almost 28 hp @ 6000 rpm, not much hope here. Well the Project Engineer say with all the confidence in world says, don't worry. Noooow advance one year to spring of '73, 5 months to production date. After many months of file here, grind there, and scarp some more, we are now at 28. 5 hp. Our chief engine is now pulling the gray side burns of his face (get the picture). So he calls me, the project engineer, and the lab super in his office and says what do we have to do to fix this. The project Engineer says he's working on it, the lab Super doesn't have a clue. Then he looks at me and says do you have any ideas. Please know that this has been an on going "discussion" between myself and the P.E. for quite a while and he didn't like my suggestions. So I open my mouth and out comes "the porting is all fudged up" the Chief looks at me, the P.E. looks at me, and the lab super is still in la la land. The last thing I hear going out the C.E.'s door is fix the Go Da thing, and the P.E. says to me you fix it. Now the porting on the original cylinders had a bridge exhaust port and two transfer ports on each side of the cylinder. I changed the angle of the transfer ports by about 30 degrees toward the back wall and went to a wide oval exhaust port. We had a set of cylinders made up and put them on the dyno. My lab super, who is still in La La land says to me "if you get any more power out of your cylinders" I will buy you a steak dinner. After starting the engine and running it @ 4000 rpm for a two hour break in, it sounded different, healthier. The moment of truth, 34.5 hp @ 6200 rpm open exhaust, a 6 hp increase. C.E. is happy. P,E. doesn't talk to me for 6 weeks and never did get a steak dinner.
more to follow.
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