Service Manual

ELECTRICAL
8 - 4 Mid-Size Walk Behind Service Manual
5. Disconnect voltage and multimeter leads from
relay terminals (Figure 216).
Figure 216
xlrelay
Solenoid
Purpose
The solenoid's purpose is simply to connect the battery
to the starter motor when the ignition switch is turned to
"START". With a solenoid we can use lighter wire and
a lighter switch to control the power to the starter. Long
lengths of battery cable are expensive and inefficient.
Location
The solenoid is located on the chassis next to the
engine.
Figure 217
mvc-061
How It Works
The solenoid has two primary parts. One is a coil of
wire wrapped around an iron core. The other part is a
bar type switch. Because it has large contact area with
the contact terminals it can easily handle the high
current loads required by the starter motor.
When 12 volts is applied to the coil, it becomes an
electromagnet. This quickly pulls the bar toward the
contact terminals and closes the switch. When power
is removed from the coil, the spring loaded bar returns
to its "normally open" position.
The solenoid closes and opens the switch very quickly.
This minimizes the "arcing" that can damage other
types of switches. The ignition switch is protected
because only a small amount of current is needed to
activate the coil.
Figure 218
xl solenoid
Testing
1. Disconnect the solenoid from the wiring harness.
2. With a multimeter (ohms setting), check to ensure
that there is no continuity between the two large
terminals.