Continuing from Virtual Tour – Part 3: Outboard Production…we will follow the assembly of Mercury Racing big blocks – those based on GM’s 502 c.i. platform.
Horsepower Highway
Jon VanDenBogart prepares to install a crankshaft in a CNC machined 502 cu.in. cylinder block.
Pre-assembled pistons and connecting rods are matched to a designated cylinder block to ensure proper fit and function.
“Horsepower Highway” is where our 525 EFI, 565, 600 SCi , 662 SCi and 700 SCi sterndrive engine family is built. One technician hand builds each engine from a bare cylinder block to a “long block” (with all the rotating and reciprocating bits fitted inside). Sub-assembly work prior to an engine build includes the rotating assembly: balancing a crankshaft, matching it with a camshaft, pistons, rings, and connecting rods for later fitment into the block.
Horsepower Highway was conceived, engineered and built in-house. It features a unique rail system and assembly fixtures used to transport cylinder blocks along the line. At each station, all the required tools and components are located for assembly. Each technician controls the speed of his build, moving the block along at their own pace. If something doesn’t look right, it is his discretion to stop right then and there. The build begins with installation of a camshaft. Next is the installation of a crankshaft, timing chain and matched piston and connecting rod sets. The bottom end is sealed with the installation of the oil pan.
The engine is rotated on its assembly fixture to enable work on the top end: The cylinder heads are installed; then push rods and rocker arms. Temporary valve covers mask the valve train prior to paint. An intake is the last component installed before the long bock goes to our paint line. Upon return from paint, it goes back on The Highway for installation of a bell housing. Color matched valve covers replace the temporaries to complete valve train assembly. Transmissions for NXT1 or NXT6 drive models are installed at this point as well.
Jon rolls a 700 SCi long block along Horsepower Highway.
It’s not everyday one sees a Nanna Yeller 565 rolling along The Highway. Mike Rebedew puts finishing touches on the 8.7 Liter long block.
Long blocks for various engine models look similar. One noticeable difference is the intake (long blocks with naturally aspirated intakes are destined to become 525 EFIs or 565s; those with pressure charged intakes will become 600/662 or 700 SCi’s). Custom color long blocks stand out, too. The “dress line” is where an engine get its true personality. Read the rest of this entry »
