At long last - Merc 666!

[R Austin]

All early (Mark series) Mercs were alternate firing twins, or stacks of them phased evenly around the crank circle. So, pulse tuned exhaust is not possible. As a result, the 666 will run Parker converging stacks. Sam can confirm, but I'm pretty sure the first pulse tuned Merc six was the 1000 in about 1962.

Otherwise, I saw a rotary valve Mark 30H at Ted Millers about 10 years ago. Painted yellow, it was likely built for alky in an attempt to beat the Koenig, the builder unknown. Similar to a Champion Hot Rod, the questions is always; how well did it work? Will take a trip to Dick Austin's thread and check out his work.

For a moment I'd given thought to turbocharging the project, because of the easy to change external pyramid reeds. But then it wouldn't have that beautiful stack of carbs, or fearsome exhaust elbows and megs. Also, deflectors aren't the best choice for forced induction because of the pistons domes. So, it stays the "666".

Tim

Your comment about the firing order changing with the 100 Merc caught my attention. Haveing been a Mercury dealer for 13 years I never saw a in-line 6 that was not cylinder pairs that fired 180 degrees apart. To the best of knowledge, that is true, thru the last in-line ( 1500 ) 6 cylinder. All in-lines share a common reed block and carb, having cylinder out of 180 dregree phase would cause havic with the induction system. However this ran a chill thru my spine because an out of phase crank could only be possible with an external reed motor, the TII X!!! I had bought a TII X crank for the Beast becuase of the seven mains. I checked that crank and sure enought, it is an out of phase firing crank. That crank will not work in the Beast because it has the siamees exhaust ports and must be 180 degree firing. Back to the planning board for new reed - bearing block replacements. Anyone need a TII X crank?

[Droll-l6]

Anyone need a TII X crank?

Drop me a PM and you can be off with it

Arne Kjetil

[Mark75H]

I checked that crank and sure enought, it is an out of phase firing crank. That crank will not work in the Beast because it has the siamees exhaust ports and must be 180 degree firing. Back to the planning board for new reed - bearing block replacements. Anyone need a TII X crank?

I was going to tell you that, but you said "no comments or suggestions"

[Ron Hill]

Chad Hill had a couple of Yamaha V-6 motors. He decided to line bore the cases and install Merc V-6 cranks, rods and pistons. Everything went fine, until we went to start it....60 degree timing base is different than a 90 degree....If it had run it would have gone rum, rum, rum rum bum bum bum, rum....Only couls us 2 grand...saved the pistons, cranks and rods for Mercs....Seemed like a great idea at the time!

[Tim Kurcz]

Hi Tim,
Engine is really getting there fast. At the rate your moving you will be running it in 4 weeks. Your making so many chips that you could sell bags of them to help with the cost of creating the work of art.

Alan

LOL! Never intending to build more than one, the castings were not fully developed. A good guess is 20% of the molds are converted to chips. The image below is just from fitting the cages. The vac is getting heavy on its wheels.......

Tim

[Tim Kurcz]

Your comment about the firing order changing with the 100 Merc caught my attention. Haveing been a Mercury dealer for 13 years I never saw a in-line 6 that was not cylinder pairs that fired 180 degrees apart. To the best of knowledge, that is true, thru the last in-line ( 1500 ) 6 cylinder. All in-lines share a common reed block and carb, having cylinder out of 180 dregree phase would cause havic with the induction system. However this ran a chill thru my spine because an out of phase crank could only be possible with an external reed motor, the TII X!!! I had bought a TII X crank for the Beast becuase of the seven mains. I checked that crank and sure enought, it is an out of phase firing crank. That crank will not work in the Beast because it has the siamees exhaust ports and must be 180 degree firing. Back to the planning board for new reed - bearing block replacements. Anyone need a TII X crank?

Somewhere in my archives is a patent filed by Mercury documenting the 120 degree spacing exhaust pulse tunig as applied to the in-line six. Will dig for it an post. Meanwhile, good luck with your "Beast"

Tim

[Tim Kurcz]

Slick! Will you make the reed holders as well?

Jeff

Even this effort is less taxing than custom building cages. A big plus is the well developed, petite OMC reed box. Also, the reeds are proven off-the-shelf items from Boyesen. Getting closer.........

Tim

[Powerabout]

why is it bikes seem to prefer one large reed per side than the outboards with many?

[Tim Kurcz]

why is it bikes seem to prefer one large reed per side than the outboards with many?

Interesting question: My guess is historical design guidelines and parts interchangeability for outboard products that last 30+ years. Motorcyles and snomobiles have a much shorter lifespan and will see more rapid design cycle (and obsolesence).

Supporting examples are the Boyesen "RAD" cages used in my "Kestrel" OMC loop triple Mod which use a single bottom leaf with three openings, and a single upper leaf covering three openings per side (six total). The same design is used by Boyesen for OMC 8-port cage replacement reeds.

[Tim Kurcz]

Your comment about the firing order changing with the 100 Merc caught my attention. Haveing been a Mercury dealer for 13 years I never saw a in-line 6 that was not cylinder pairs that fired 180 degrees apart. To the best of knowledge, that is true, thru the last in-line ( 1500 ) 6 cylinder. All in-lines share a common reed block and carb, having cylinder out of 180 dregree phase would cause havic with the induction system. However this ran a chill thru my spine because an out of phase crank could only be possible with an external reed motor, the TII X!!! I had bought a TII X crank for the Beast becuase of the seven mains. I checked that crank and sure enought, it is an out of phase firing crank. That crank will not work in the Beast because it has the siamees exhaust ports and must be 180 degree firing. Back to the planning board for new reed - bearing block replacements. Anyone need a TII X crank?

Sorry to hear about your dilemma. Better to find out about it sooner than later. I'm hoping another Merc crank will do the job! Good luck,

Tim