CLICK ON THE THUMBNAILS FOR THE BIG PICTURES

THIS ALL STARTED WITH A VISIT TO RON HILLS WEBSITE AT WWW/BOATRACINGFACTS.COM, THE THREAD OF MARK 40-H. HERE I FOUND THE VAN WEELES IN THE PROCESS OF BUILDING A MODIFIED VERSION OF THE 40-H BUILT FROM 1953 THRU 1955. THIS THREAD HAS A LOT OF INTERESTING INFO ON MERCURY MOTOR MODS. WELL, I HAVE A LOT OF STUFF LYING AROUND AND I THOUGHT HEY, I CAN DO THAT!!

PICKED THE BEST SANDCAST BLOCK OFF THE SHELF, HERE'S WHAT I FOUND IN THE WATER JACKET! AS YOU CAN SEE, IT PAYS TO CHECK EV-RY-THING!

CLEANED UP THAT MESS AND SENT THE BLOCK OFF TO DOUG KAY FOR SOME MACHINE WORK. WHEN IT CAME BACK IT WAS A DIFFERENT ANIMAL. SORT'VE LIKE BUILDING UP A 350, YOU MAKE THE RIGHT MODS AND USE THE GOOD PARTS.

THE CRANKCASE CARB OPENINGS ARE NOT WELDED. A INSERT WAS ADDED WITH EPOXY. BY USING THIS METHOD THERE IS NO DISTORTION OF THE HOUSING.

THE CRANKTRAIN IS FROM AN OLD QUINCY C MOD ENGINE, THE ASSEMBLY WAS BALANCED AND PLATES ADDED TO THE COUNTERWEIGHTS TO HELP WITH BALANCE AS WELL AS BASE PRESSURE.

THE BRASS REED BLOCKS FROM A 44CID MERC 500 WERE USED. THE BLOCK BOLT LOCATIONS WERE MOVED SLIGHTLY TO LINE UP WITH THE OLD SANDCAST CRANKCASE.

I LEFT THE STOCK REED VALVES ALONE AS THE INDUCTION BREATHING IS NOT AN ISSUE HERE, PLENTY ADEQUATE.

I DECIDED TO GO WITH A KF-9 MIDSECTION AND LOWER, AS THIS MOTOR IS INTENDED TO BE USED AS A FAST MOVER ON A 13.5 FOOT LIGHT FIBERGLASS BOAT LIKE I RAN AROUND THE LAKE IN AS A KID. THE SWIVEL AND CLAMPS ARE STOCK MARK 50 AND FIT THE KF/KG AND H TOWERS PERFECTLY. THE GEARCASE HAD A BROKEN SKEG, DOUG KAY WELDED AND CONTOURED A NEW ONE FOR ME.

 ASSEMBLING THE GEARCASE

FINISHED, READY TO INSTALL. PUT A SPEEDISLEEVE ON THE DRIVESHAFT.

SO NOW IT'S TIME TO MAKE BIG ONES OUT OF LITTLE ONES. THE MAGNETO WILL BE A FAIRBANKS MORSE LIKE THE ORIGINAL, WITH THE PLUG LEADS ROUTED AROUND THE INTAKE SIDE OF THE BLOCK. KA24 CARBURETORS INSTALLED, MODIFIED TO ADJUSTABLE HIGH SPEED JETS.

THERE'S LOTS OF PARTS IN THESE OLD DESIGN MOTORS. THE ABOVE IS JUST THE STUDS FROM BLOCK TO CC AND THE 4 INDIVIDUAL PORT COVERS!

SINCE THIS IS A PLEASURE BOAT RIDE I'M MAKING IT ELECTRIC START! THIS ENGINE HAS A "SMALL TAPER" CRANKSHAFT AND IN ORDER TO ACCOMPLISH THIS WITH AVAILABLE DIRECT DRIVE STARTERS I NEEDED A 57 MARK 55 FLYWHEEL. SEARCH ENDED DOWN AT THE LAKE DORA AYBC MEET WHERE GOOD FORTUNE TURNED ONE UP. NEW SOLID BRASS BUSHINGS WERE INSTALLED IN THE MIDSECTION AND A NEW PIVOT SHAFT WAS FITTED.USED LOCKNUTS TO SECURE THE POWERHEAD TO THE MIDSECTION AS WELL AS ON THE GEARCASE STUDS. THE MARK 50 LOWER PAN IS A SANDCAST (REMEMBER, SANDCAST IS FAST - -!! ) VERSION AND THE MOUNTING FLANGES WERE MACHINED SO I WAS ABLE TO GO METAL TO METAL WITH SEALER BETWEEN THE PAN AND TOWER.

THIS IS A WORK IN PROGRESS, CHECK BACK AND SEE IT RUN!!

THE BOAT IS IN THE BACKGROUND, WE'LL HOPEFULLY TURN IT BACK OVER THIS WEEKEND 5/15/2009

GO HERE TO SEE THE WORK BEING DONE ON THE BOAT.

ASSEMBLY CONTINUED - -

AND HERE'S THE FINISHED PRODUCT!