Ecospeed™ Engine; Positive Air Shutdown (Pas) (If Equipped); Test The Pas; Reset The Pas - Generac Power Systems MAGNUM MLT4060MVD Owner's Manual

ECOSpeed™ Engine
This unit is equipped with an ECOSpeed engine that runs
at variable speeds depending on the applied operational
load. Operating temperature remains constant regardless
of engine speed or applied loads.
Refer to Operation for more information.
Positive Air Shutdown (PAS)
(if equipped)
See Figure 2-5. This unit may be equipped with a
positive air shutdown (A) on the air intake. The PAS
system automatically stops the engine if speed exceeds
2100 rpm. Engine overspeed can occur if the
atmosphere contains elevated levels of combustible
propane or natural gas.
A
Figure 2-5. Positive Air Shutdown
The PAS system stops the engine by closing an internal
valve and obstructing intake air. Shutdown is triggered
automatically by an output from the controller, manually
by pulling the T-handle (B), or by pressing the emergency
stop button on the control panel.
The reset knob (C) rotates 90 degrees to block airflow. If
the knob is parallel to the pipe centerline (as shown), the
valve is open. If the knob is perpendicular to the pipe
centerline, the valve is closed and airflow is blocked.

Test the PAS

Test the PAS at least once a month to ensure optimal
valve performance.
Verify the engine is OFF before testing the PAS.
There are two methods of testing. NOTE: The main
power and controller must be ON for each method.
Pull the T-handle. (NOTE: The valve must be open
1.
before testing.)
Press the emergency stop button. Testing the PAS
2.
triggers an actuator, closing the butterfly valve
inside the valve body. An audible click can be
heard when the actuator engages. Confirm that the
valve is closed by verifying that the knob has
rotated perpendicular to the pipe centerline. If
Owner's Manual for MLT4060MVD Light Tower
valve does not close, contact Generac Mobile
Products Technical Support.

Reset the PAS

IMPORTANT NOTE: Before resetting the PAS, turn the
Control Power switch OFF (O). This will prevent
unexpected engine start-up during the procedure.
Rotate the reset knob (C) and hold it in place while
1.
pulling the T-handle until knob rotates counter-
clockwise into plunger detent. An audible "click"
indicates the knob has seated properly
Verify that the knob is parallel to the intake pipe
2.
centerline.
Release T-handle, and then release knob. Knob
3.
should remain parallel to the intake pipe centerline.
Lower Radiator Hose Heater
B
(if equipped)

Use and Maintenance

The lower radiator hose heater is designed to enable
engine start-up in extreme cold weather conditions by
warming the engine coolant. While the heater is designed
to be operated overnight if necessary, two to five hours of
heating just prior to starting is usually sufficient for proper
C
engine starting.
NOTE: Use the lower radiator hose heater only in its
designated location. Improper use can damage the
engine.
Perform the following steps when operating a unit
equipped with a lower radiator hose heater.
Verify the unit is level so as to maintain proper
1.
orientation of the heater while it is in operation.
Verify the cooling system is full of the proper
2.
mixture of water and engine coolant before each
heater use.
Use only an undamaged, outdoor rated, three-
3.
prong grounded 120VAC extension cord with a
minimum amperage rating of 10A. Connect the
cord to a properly grounded 120VAC, GFCI outlet.
Before starting the engine, unplug the extension
4.
cord from the power first, then unplug the heater
cord set from the extension cord.

Diesel Fired Block Heater

See Figure
inside the cabinet. Coolant is drawn through the heater
by an internal electric pump, and warmed by a diesel-
fueled burner. Heated coolant is then circulated through
the engine block and returned to the heater where the
cycle is repeated.
General Information
2-6. A diesel fired block heater is located
17