The saga of the construction of a 7 HP Hercules half base
screen-cooled engine replica continues. The cart has been painted
dark red with dark hunter green wheels. A copy of the original
stenciled design has been put on the cart frame, and it has been
moved forward from center so the flywheels will not obscure it when
the engine is mounted.
An oaken box seat has been made with room for the battery and
coil. There is a removable tool tray above the battery and coil
area. The seat itself looks nice, but it will be found to be too
narrow for most of us to sit on.
The screen cooler will be positioned at the rear of the frame
and held down with four long ‘J’ bolts. The custom-made
fuel tank has been mounted between the frame rails, too. All of
these features mentioned so far can be seen in the first picture
(see Photo #1).
Photo #2: Wooden patterns for foundry work. Smaller cover to
left covers larger cover at right, which goes where water hopper
Since a hopper-cooled engine is being converted to a
screen-cooled, it is necessary to provide a different water jacket
top for the cylinder. The next picture (see Photo #2) shows the
wooden patterns that have been made and sent to the foundry. The
large cover will be held to the cylinder by six stud bolts screwed
in the bottom and fastening to the same six lugs that held the
water hopper on. The smaller cover is for the opening of the larger
cover. It will be held on by six cap screws. The small bump in the
middle will be drilled for -inch pipe. These two patterns were
copied from pictures of an original engine.
Photo #3: Crank guard made from heavy-duty sheet metal. A bead
is rolled into the metal to stiffen the guard.
The final picture (see Photo #3) is my attempt at a sheet metal
crank guard. I have never seen a real one, so this one is made from
heavy sheet metal to best match what can be seen in early catalog
pictures. A bead had been rolled about an inch in from the edges to
help stiffen and decorate it. The ends of the crank guard are held
on by one 12-24 screw on the rear of the cylinder and two on the
lower rear of the base.
Along with the above, several other parts have been repaired or
modified, including the rocker arm and adjusting bolt, side rod,
governor, valves and springs, and detent lever. A reproduction
igniter has been acquired, along with a right-angle
cylinder-priming cup. The igniter trip and bracket were obtained
from a parts vendor. All these things will all show up as this
project continues. Stay tuned.
Glenn Karch is a noted authority on Hercules Engines.
Contact him at: 20601 Old State Rd., Haubstadt, IN 47639, or