(Mike Hill summary from Jerry Hale's post 10 years ago)
My name is Jerry Hale, and I was the project engineer for Mercury’s (Black Max) 2-liter, 2-stroke, V6 outboard. To authenticate my position, you can reference the following patents in my name (David Jerry Hale, as I go by my middle name): Patent #4,092,958 (Internal Combustion Engine), Patent #4,066,057 (Cylinder Head Mounting Apparatus for Internal Combustion Engines), and Patent #4,082,068 (V-Engine Cooling System Particularly for Outboard Motors and the Like). All patents are assigned to Brunswick Corp and pertain to the V6.
There seems to be interest in how this engine came about, so I thought I would document what happened 43 years ago before Alzheimer’s sets in. I intend to share this in small, weekly installments as best as I can manage.
The project began in January 1970 at Mercury’s Outboard Engineering Plant #6 in Oshkosh, WI. The initial study presented to me aimed to determine the optimal engine configuration (inline, V, or opposed) and the number of cylinders. It was to be a looper with 2 liters of displacement, capable of being bored for an additional 10% increase, featuring a die-cast block, and designed for the lightest weight and smallest possible size. The power goal was at least 10% higher than the 1350 (135 HP) inline-six then in production, targeting 150 HP.
Keith and Ralph were both part of my team at the beginning of the 951 (V6) project, though I do not recognize the Triechel name. He is not listed on the Plant 6 honor roll, which includes everyone who ever worked there, including notables like Carl Kiekhaefer, Charles Alexander, Charlie Strang, and several guest workers such as Tony Bettenhausen, Briggs Cunningham, Tim Flock, Bill France, Ted Jones, Jack Leek, Maury Rose, Red Vogt, “Gorgeous George” Wagner, Lee Wallard, Phil Walters, and Gar Wood Jr. These individuals were all gone before I arrived in March 1965. Some were associated with Mr. K’s car racing in the 1950s, remnants of which were still visible in the garages, including car lifts and valve grinding equipment.
Ron Anderson and Joe Harrelson joined the V6 project shortly after it began and contributed significantly. Ron transformed the production “Black Max” into the T3 race engine and later opened a prop shop and marina in Seattle. Joe became a college professor in California, teaching engine design, and designed a large V4 engine used in a world motorcycle speed record attempt.
Other key figures included Bob Johnson (RTJ), manager of Outboard Engineering, who provided the engine requirements list. It is likely he initiated the “Black Max” V6 idea. Carl Kiekhaefer, by then, was mostly out of the picture and likely unaware of the new engine.
Contributors also included Dick Lanpheer (sound and vibration engineer), Al Tyner (board man and detail designer), Dave Kusche (cowling design), Art Miller (stylist), Elmer Croisant (undercarriage), Bob Schmeidel (electrical), and Jim Meininger (carburetion).
Bob Johnson’s handwritten spec sheet from January 1970 outlined the objectives:
OBJECTIVE: RAISE MAX. POWER 10% = 150HP.
1. A 10% displacement increase is inappropriate – no room for future increases, bore increase will increase detonation problems.
2. A 20% displacement increase fits the 2-liter class.
3. Bore: 2 7/8" (1350 size), Stroke: 2.35" = 15.25 cu. in.; 8-cyl = 122 cu. in., 6-cyl = 91.5 cu. in., 4-cyl = 61 cu. in.
4. Develop loop cylinder to avoid cross-scavenged problems.
5. V configuration supports loop cylinder spacing.
6. Design for a potential 10% displacement increase later (bore only).
7. Target lightest weight and smallest package size.
Bob was thinking about using the same parts for economy of scale, even considering a 2-liter V8, which I found impractical. For racing, a six-cylinder arrangement was ideal for exhaust pulse tuning.
After deciding on a 60° V6 configuration due to its compact design and optimal characteristics, I needed to study loop-scavenged engines, choosing the Husqvarna 360 motorcycle as my model. I tested the engine, impressed by its power characteristics and torque band. I then performed flow tests using a “Jante Fixture,” named after the German engineer Alfred Jante, who developed the method for analyzing transfer passages.
“Old Blue,” the first sand-cast V6, proved to be reliable and powerful, reaching up to 204 HP at over 6,000 RPM during tests. This engine became legendary and survived decades, eventually rediscovered in a neglected state before I restored it partially.
Further technical challenges involved compacting transfer passages, designing the cooling system, and creating the cylinder head and piston shapes. Innovations included using a hemi head combustion chamber, double-pass cooling for even temperature distribution, and designing a die-cast block with blister liners to form internal passages.
The original clam-shell cowl design allowed easy access to the engine components but was later replaced with a top cowl design due to user complaints. The ignition system also evolved from a distributor-based system to a six-coil, distributor-less design, significantly delaying production.
Despite setbacks, including OMC’s unexpected release of their 200 HP V6, Mercury’s “Black Max” prevailed, marking its place as an engineering success and remaining in production decades later.
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