Hale Fyr Port - Manual (Page 9)

MOUNTING BASE:
The mounting base is an intermediate part to which the engine is attached with
three shock-vibration isolation mounts. The base is then attached to the two skids.
The mounting base has the overspeed control switch, priming pump mounting
clamps (skid version) and Hale nameplate attached to it.
OVERSPEED CONTROL:
The overspeed switch control assembly is a safeguard against overspeeding of
the engine. The overspeed switch is attached to the mounting base of pumping unit
below the carburetor. Attached to the front of the overspeed switch is a flexible
transparent hose that is connected to the nozzle plate (riveted to the engine fan
housing). Connected to the back of the overspeed switch are two wires; one goes to
the engine’s ignition coil, the other goes to ground (engine). The switch senses the air
pressure generated by the engine’s cooling fan.
When the engine reaches a speed in excess of that which would normally occur,
the fan air pressure generated will be sufficient to cause the switch to close;thereby
grounding the solid state ignition. The engine speed will decrease until the air pressure
reaches a lower trip point, reactivating the ignition system and the engine will
accelerate. The engine will decelerate and accelerate alternately until the operating
conditions are returned to their normal mode.
WRAPAROUND FRAME:
The wraparound frame protects the pump, engine and fuel system from damage
caused by normal handling. The frame also serves as a convenient means for
transporting the FYR PORT unit over long distances.