Mercury Mark 5H.....Never before seen.

[Mini Max]

Mercury Mark 5H.....Never before seen. That's because Mercury never made one. However, I always wanted the smallest green onion with an H tower. These engines are plentiful and I think the kids at the cottage could have some fun. Dad too.

Every week I make large composite parts with glass/epoxy and there is always a small amount of catalyzed epoxy and glass wasted. I have been scratching my head for something to make with it.

I was thinking of making a mold to do an H tower for the Mark 5 out of glass that fits the standard transom clamps and gear foot. In appearance proportionally smaller than the one on my KG7H. Then make a nose cone for the bullet with a low water pick up.

Questions are;

Any suggestions for props?
Any hop up tips?

I'm thinking to be as minimally invasive as to mods so that the engine could be returned to stock if desired some day. Except for Dad's motor of course.

[Amod20HRacer]

Mark Suter has a Mercury Mark 5 Racing Engine. I believe it was built by John Schubert a few years back. I've never seen it run but it sure is a cute little fella!! Hopefully someone on here will chime in with more information and possibly a few pictures.

Austin Duggan, 78M

[Tim Chance]

I have attached a photo of the Mercury 60-J that my son raced some 35 years ago. Wouldn't a MK-5 powerhead just bolt up to this racing lower unit? Don't know - just asking. Still have the motor after all these years.

[Amod20HRacer]

No a Mark 5 powerhead will not bolt directly to a 60J lower unit. The powerhead on a Mark 5 works as the swivel on the saddle bracket. It's a rather unusual power head.

[A/B Speedliner]

I have a Mark 5 on a 1959 JU Sid Craft listed for sale on my web page www.aeroliner-boats.com. John Snell rebuilt the engine.

[BRIAN HENDRICK]

This purported back door[skunk works] M5HA 'Special' was displayed at Tomahawk recently. An alky motor with open exhaust. Maybe an attempt at a Class 'M' motor as that alky class was still active at that time.
The crankcase on this one looks a bit odd;
-more like a KE4 ? :confused:

[Amod20HRacer]

Here are a few pictures of Mark Suter's Mercury Super 5 racer. These pictures were taken at his AOMCI meet during the fall of 2007.

http://thumb12.webshots.net/t/62/562/1/32/55/2996132550099263452atavHi_th.jpg (http://rides.webshots.com/photo/2996132550099263452atavHi)

http://thumb12.webshots.net/t/64/564/0/66/7/2560066070099263452jacwbB_th.jpg (http://rides.webshots.com/photo/2560066070099263452jacwbB)

[Mini Max]

I am never going to say never again. Cool photos.

I tear into the first Mark 5 tomorrow night.

Unusual engines to add to the list. This one, the powerhead is fixed, only the tower steers.

<img src="http://www.forumpictureprocessor.com/pictureprocessor/images/omc.jpg">

[A/B Speedliner]

I have about 100 pounds of Mark 5 parts including powerheads, mid sections, lower units and clamp brackets as well as numerous other parts. If anyone is interested I will sell them at a reasonable price. I can post pictures if there is any interest.

[mac19f]

"Unusual engines to add to the list. This one, the powerhead is fixed, only the tower steers."

With this setup any frictional losses in the gearcase result in driveshaft torque being transferred to the steering.. Not a good idea.

[Mini Max]

I have been scratching my head abot what you are saying. For sure with out the mass of the powerhead increasing the inertia that the torque steer or the moment from the prop in the water acts upon, I would think you would "feel" it more. I have lead weights in the ends of my motorcycle handle bars that help in that way.

With a 5% loss acting over a very small moment arm (1/2 the diameter of the pinion gear) it can't be a big component. At least not compared to the prop steer from the propeller. Maybe its a good thing if the torque from the gears was in the opposite direction to the prop? I tried diagraming it and seemed to me like it was not. Then I got to thinking about that the normal lower units pivot point is forward of the verticle drive shaft. Maybe with this engines pivot being the same as the drive shaft, the prop has a shorter moment to torque steer and the net result if less.

Mac19f, what do you think?