Facts about Evinrude/Johnson racing outboards made my OMC

[Instigator]

My guess would be machinist die.

Shim, assemble, rotate, disassemble, check contact area, re-shim, reassemble etc.

Would agree on the art part also.

To Shim properly to ensure "equal loading" to me, seems to me to be as much art as science. How can one "ensured equal loading" were the gear case obstructs the view (measurement gauge readings) of the contact areas?

I wonder if the experienced Technician, is relying on his feel when he turns the shaft by hand.

[STEVERINO]

EVINRUDE STILL HOLDS THE RECORD - The record for the fastest speed for an outboard powered boat is 176.556 mph (284.14 km/h) set by Bob Wartinger (USA) in a Karelsen hull powered by a 3.5 litre Evinrude V-8 on the Colorado River neat Parker, Arizona on November 30, 1989. Running at close to 10,000rpm with a overdrive gearcase, this incredible motor powered a 20 foot, 3-point hydroplane to a 2-way average of 176.556mph. During testing it easily exceeded 190mph but was damaged after hitting an object in the water. It was expected to exceed 200mph until than unfortunate incident.

Attachment 466310

It was Bob Hering that first drove that outfit maybe you know why he gave up driving it.

[STEVERINO]

Ward Cox was the gearcase man for OMC when I was involved. He rebuilt each gearcase after every race

I new Ward Cox and shared many a beer with him a very quiet guy but always good company is he still around today?.

[WaterZebra]

My guess would be machinist die.

Shim, assemble, rotate, disassemble, check contact area, re-shim, reassemble etc.

Would agree on the art part also.

There was an engineering spec for these twin pinion set ups. The spec said to obtain 15 inches of torque at a specified hand-turned RPM rate. I think science morphed into art with these technicians having done this so many times that they could "feel" the same requirement rather than setting up a bending beam inch/pound torque wrench and spline adapter. I had a Boeing stress engineer ask what "feel" meant in a design spec one time. It took 20 minutes to answer his question.

[2us70]

Building up any lower unit is much like building up a auto rear end. Even a stock "fishing motor" lower unit requires some care. If you are going to race it it better be right. I can still recall all the speedmaster racers constantly checking gear lash on their prop shafts and keeping track of how much time they had on each unit.

[lars strom]

It was Bob Hering that first drove that outfit maybe you know why he gave up driving it.

Dont know for sure but the 176+MPH record run 1989 was by GG and Second Effort. Not sure how the relationship between Hering & GG was.
As we all know GG did things his way.

[Instigator]

I was actually thinking of the rotation torque aspect too.

Hilarious about the engineer.

I have a friend who is a genius tool maker and I tease him telling him, dude, I could ask you to machine me a 12” aluminum cube and you would call me 20 times asking questions.

I had a Boeing stress engineer ask what "feel" meant in a design spec one time. It took 20 minutes to answer his question.

[2us70]

Dial inch pound wrench, dial indicator and some gear marking compound. On the stock "fishing motor" units if you did it right you never had to do it again. I never worked on a "Speedmaster" but I guess they lacked room for enough gear to handle the load. The stock units were way over built. I had one failure in 13 years. That was in a first year prop jet 500. The rear bearing carrier broke at Key West in very shallow water. I recovered all the parts except the cam follower and proceeded to learn how to build those things.

[WaterZebra]

Dont know for sure but the 176+MPH record run 1989 was by GG and Second Effort. Not sure how the relationship between Hering & GG was.
As we all know GG did things his way.

The gossip story goes that Hering had the propeller that made getting to 200 MPH are sure bet but would not part with it because of past friction with GG.

[lars strom]

[Rotary John]

I don't recall Ward ever putting a torque wrench on a gearcase. He had a "feel" and knew when it was right. I don't recall either a gearcase failure when I was involved, V-4, V-6 or rotary.

[Rotary John]

Last I heard Ward and his wife lived in FL. Ward didn't/wouldn't use a computer so his wife did all that. I talked to her several-several years ago and Ward was just fine. That's all i know. Most of the old OMC race crew have passed. I think Mike Gaultney is still around.

[lars strom]

Over my 20 years of racing OMC I very seldom run in to gear-case problems.
From production gear-case to racing gear-cases like X-115, mod 50, CCC V6 (2 liter and 2.6 liter) and the F1-V8
I did break a prop. shaft during a Offshore race with a production V8.
Did have some issues with the nitro gear-case 1975..not sure why.
Overall OMC gear-cases was in my opinion extremely good..and the CCC & V8 racing gear cases very sexy..!!

Pretty sexy picture of the Evinrude-Johnson F1-V8 racing gear case above.

[STEVERINO]

The gossip story goes that Hering had the propeller that made getting to 200 MPH are sure bet but would not part with it because of past friction with GG.

Rumours had it that Hering had been keeping prop testing information to benefit himself not disclosing them to GG that was around 1975/1976 but rumours only.

[lars strom]

Rumours had it that Hering had been keeping prop testing information to benefit himself not disclosing them to GG that was around 1975/1976 but rumours only.

Thanks STEVERINO..Pretty sure you made a typing error..must be 1985/1986..

Bob Hering, U.S.A., Parker Dam, Evinrude V8, 169.53 MPH