Table of Contents
Advertisement
Sec. 8
Page 144
GM COACH MAINTENANCE MANUAL
DIESEL ENGINE ACCESSORIES
SOLENOID LEVER
Figure 4-Engine Stop Solenoid and Mechanism
SOLENOIDS
All engines are equipped with an emergency
stop solenoid mounted on blower intake.
An en-
gine stop solenoid (fig.
4)
is also used as stand-
ard equipment, however; latter solenoid is not
used on coaches equipped with air operated
in-
jector rack shut-off (fig. 5).
ENGINE STOP SOLENOID (Fig. 4)
Engine stop solenoid is mounted on engine
governor housing and connected by linkage to gov-
ernor cam lever. When energized by engine stop
switch, the solenoid pulls on lever which operates
cam and allows spring on accelerator cross shaft
to move accelerator lever to "No-Fuel" position.
EMERGENCY STOP SOLENOID
Emergency stop solenoid, mounted on blower
intake, is used to release a valve to shut off air
supply to engine, thereby stopping the engine.
Solenoid is energized by emergency stop button
at instrument pnael.
Energized solenoid acts to
release a valve which is forced into closed posi-
tion by spring.
NOTE: After stopping engine by means
of emergency stop solenoid, the engine can-
not be started again until valve is opened
and reset manually.
SOLENOID MAINTENANCE
Solenoids require no maintenance other than
keeping contact points and terminals clean and
~/
tight.
Always check action of solenoid if it has
been removed and reinstalled.
If unit fails to
function, first check switches, relay (when used)
and wiring before working on solenoid. Only test
to make on solenoids is to check pull of solenoid
coils with suitable equipment.
Refer to "Specifi-
cations" later in this section for test data.
AIR OPERATED INJECTOR
RACK SHUT-OFF
Injector rack shut-off, operated by an air cyl-
inder, is used as special equipment on some
coaches. Figure 5 shows air cylinder and linkage
installation.
Air supply is controlled by magnet
type valve which is energized from engine control
switch circuit. Air cylinder is bolted in place at
engine cylinder head, and adjustable rod transmits
piston movement to lever installed on end of in-
jector control tube.
When engine control switch is in "RUN" posi-
tion, air pressure is• exhausted from air cylinder
permitting injector racks to be moved to "full
fuel" position for normal operation. When control
switch is turned off air is admitted
to
air cyl-
inder and piston moves to end of travel thereby
forcing injector racks to "No-fuel" position caus-
ing engine to stop.
Air is applied to cylinder
during the time control switch remains in
off
position.
Advertisement
Table of Contents
