Hercules Engine News

By Staff
article image

20601 Old State Rd. Haubstadt, Indiana 47639

Rebuilding the governor on Hercules built engines is usually a
simple matter if a step by step procedure is followed. Although
there are slight differences between the governors used on the one
piece block small engines and the larger three piece block engines,
the steps are the same. There are also a few differences between
the earlier governor and the later ‘H & S’ model
governors. To complicate matters further, many engine governors
today are mixtures of the different model parts put together.

The accompanying illustration, although for the larger engines,
shows all the important parts referred to in the article to

Begin with the removal of the entire governor assembly from the
engine. On most engines, an offset screwdriver will be a big help
to reach in and loosen the slot head bolts used on most engines. Be
careful to not let the governor spindle rod fall out (if it is of
the ‘H & S’ type). If the end of the rod falls out, you
can usually find it, but the little ball will bounce away and hide

Remove the governor weight pins. If they are worn, make new ones
from stock of the original diameter
(3/16‘). Peen one end and drill a cotter
pin hole through the other end.

Remove the governor spindle rod, spring and any spacer washers.
The head of the spindle rod may have notches worn in it where the
governor weight fingers touch it. The other end of the rod may be
worn off from turning against the detent arm finger. A new rod can
be made from a ‘ diameter carriage bolt. Make the new rod
slightly longer than the old one.

Remove the pin that holds the detent lever and the speed change
body on. If it is worn, replace it. The detent arm finger may also
have a depression worn in it where the spindle rod turns against
it. Braze or weld it back up and grind to original shape. Some
detent arm fingers have a wear button that may need to be replaced.
The ‘H & S’ governor detent arm may need an new
adjustment screw. Sometimes a notch is worn in the opposite end of
the detent arm where it touches the speed change lever. This may
also need to be filled in. There is a small spring that causes the
detent to unlatch for the power stroke. It only needs to be strong
enough to push the detent lever out. The speed change lever bottom
protrusion may be worn off and require building back up.

Remove the governor gear from the shaft by turning
counterclockwise. It has right hand ‘ NF threads. Be sure to
loosen the governor gear retaining screw if it has one in the gear
collar. Be careful not to break an ear off the governor shaft.
Clamp the ear end in a vise and use a pipe wrench on the gear. If
it doesn’t come off easily, use a propane torch and heat the
gear. That usually does it. There should be a brass thrust washer
between the gear and the housing. It is often gone or worn too
thin. Make a new washer just thick enough so it doesn’t bind
when the gear is retightened. Unless the governor body and shaft
have been broken, they are seldom too worn to use.

Finally, the detent blade should be straight and the end ground
to an 80 degree angle so it will catch on the block. The catch
block is reversible if badly worn. It can be refaced to a new 85
degree angle by using a narrow abrasive disk on a Dremel type

Reassemble the governor using a few drops of oil at all moving
points. Loosen the detent blade retaining screw and turn the detent
blade adjusting screw until the blade just goes in behind the catch
block when the side rod is all the way out (on the high point of
the cam).

Although the information above pertains to the Hercules built
hit and miss engines, the same guidelines can be used on many other
brands of engines too. Coming next rebuilding the head on the one
piece block 1 to 2 HP engines

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