ELECTRIC PROTECTIVE SYSTEM
4W2218 ELECTRONIC SPEED SWITCH (ESS)
1. Verify button. 2. Reset button. 3. "LED" overspeed light. 4. Seal screw plug (overspeed). 5. Seal screw
plug (crank terminate). 6. Seal screw plug (oil step).
particular engine rating, find the specified rpm in column
OIL STEP CALIBRATION
for Oil Step Speed Setting. Run the engine at this
1. Remove the lockwire and seal from seal
screw plugs (4), (5) and (6). Remove seal screw plug (6)
from access hole for the oil step adjustment screw.
5. With the engine running, look into the oil
step adjustment access hole. A red "LED" (light emitting
2. Use a small screwdriver and lightly turn oil
diode) light will be on. After an 8 to 10 second delay,
step adjustment potentiometer 20 turns in the direc- tion
positive (+) voltage will be seen at terminal ESS-13.
opposite of "MAX ARROW" (counter- clockwise). This
Now turn the oil step adjustment potentiometer clockwise
will lower the oil step speed setting to its lowest value.
until the red light in the oil step access hole goes out.
When the light goes out, this indicates that the oil step
NOTE: The oil step adjustment screw is made so it can
rpm setting is above the present running rpm of the
not cause damage to the potentiometer, or be removed,
engine. Slowly turn the adjustment poten- tiometer
if the adjustment screw is turned too many turns in either
counterclockwise until the light comes back on. After an
8 to 10 second delay, positive (+) voltage will be seen at
3. Use a 6V7070 Multimeter (or a voltmeter of
same accuracy) to check for positive (+) voltage at
6. When the oil step setting is correct, install
terminal ESS-13 [negative (-) voltage is at terminal ESS-
seal screw plug (6) into the adjustment access hole for
the oil step function. Tighten plug to a torque of 0.20
0.03 N-m (2 + .3 lb. in.). If all other adjustments are
4. Make reference to SPEED
complete (overspeed and crank terminate), install
SPECIFICATION CHART (Part of PROCEDURE D).
lockwire and seal.