TM 5-3895-385-23-1
0003
Hydraulic Systems
The BMPM on-board QSB 4.5 turbocharged Tier 3 electronic diesel engine drives hydraulic pumps and gear
drives to provide propulsion and power to hydraulic subsystems on the BMPM.The BMPM hydraulic system
drives numerous BMPM functions. Propulsion is hydraulically transmitted through a torque hub and is
independent of other hydraulic systems to prevent drive power loss during operation of other hydraulic functions.
Screed raise, lower, and extension tasks use hydraulics, as do hopper wing opening and closing. The dump truck
hitch, screed, and extensions, as well as the generator used to heat the screed, are all hydraulically powered.
The BMPM has an air-cooled reservoir that maintains a hydraulic tank oil temperature below 200 degrees
Fahrenheit (F) (93.3 degrees Celsius (C)), with an ambient temperature of 120F (49C) while under sustained
operations. The hydraulic systems each have gravity-fed drains in locations that provide easy access for quick
service of engine and transmissions or fluid replenishment of hydraulic systems. On-board diagnostics are
programmed to monitor and display all engine and hydraulic subsystems simultaneously and provide alerts for
any given element that exceeds preset thresholds.
Engine Starting
The engine is started by means of a keyless engine switch found on the left pedestal assembly control. The
starting system consists of two 12-volt (V) batteries connected in series to produce 24 V of electric power, a
starter, a 24-V battery-charging alternator, a magnetic pickup for sensing engine speed, and related switches and
relays required to control the starting system. For engine cranking, battery power is supplied to the starter motor
through the starter solenoid, which in turn is controlled by the cranking relay. The starter then engages the engine
flywheel, causing the engine to turn over. While the engine runs, the batteries are continually being recharged by
the battery-charging alternator.
The BATTERY DISCONNECT switch must be in the ON position to start the BMPM.
Electrical System
The BMPM electrical system (engine included) is designed on a 24-Volts Direct Current (VDC) platform with
alternator, providing power to all onboard systems simultaneously. A single keyless engine switch is located on
the left control pedestal, and a North Atlantic Treaty Organization (NATO) STANAGA-4074 Type 1 slave
receptacle is included.
Work Lights
Six circuit breaker-protected work lights controlled by a weatherproof switch are installed on the BMPM. Two of
the lights are directed into the receiving hopper and feeders, two are directed into the area behind the compacting
unit, and two are directed into the auger area.
Backup Alarm
The BMPM has a backup alarm that produces a sound level of 107 decibels (dB) as measured within 10 ft (3 m)
of the operator platform control pedestal. This is 10 dB louder than the background noise of the operating vehicle.
Additionally, a manually-controlled rotating yellow light can be used to help identify to surrounding personnel that
the vehicle is in motion.
