HYDRAMECHANICAL PROTECTIVE SYSTEM
PROTECTIVE SYSTEM WITH ENGINE SHUTDOWN FOR OVERSPEED ONLY, ALARMS FOR OTHER FUNCTIONS
1. Oil line to air inlet shutoff actuator. 2. Return line from air inlet shutoff actuator. 3. Oil line to thermostatic
pilot valve. 4. Return line from diverter valve. 5. Oil line to diverter valve. 6. From two-way valve at the diverter
valve to drain. 7. From diverter valve to governor (fuel) shutoff actuator. 8. Oil pressure switch for alarms.
AIR INLET SHUTOFF CHECK
Operate the engine at low idle and pull the red,
emergency knob. The air inlet shutoff valve must close
and stop the engine. Low oil pressure and high coolant
temperature alarms should also be activated, if so
The fuel shutoff actuator must also move the
governor and fuel control linkage to the "SHUTOFF"
PROTECTIVE SYSTEM OIL LINES
3. Oil line to thermostatic pilot valve. 5. Oil line to
After this test has been performed, the air inlet
diverter valve. 6. From two-way valve (at the
shutoff valve must be opened. Also, the startup
diverter valve) to drain.
override valve must be operated to release hydraulic
pressure from the governor shutoff actuator before
START-UP OVERRIDE VALVE CHECK
the engine can be started again.
On an engine with an air start system, start and
operate the engine at low idle. Loosen the drain line
from the two-way (palm) valve. There should be no oil
present. If there is any oil flow, the valve has failed and
replacement is necessary.