RUMBLE HOG RH7500, Operation Manual

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Section 2 - Rumble Hog Systems
2.19 engine & transmission
Overview
Power is transferred from the engine to the drive-
train and cutting system through the chassis
transmission and the OMSI gearbox.
The OMSI gearbox provides two modes of opera-
tion that can be selected by the operator; TRAVEL
mode for transporting the machine on the highway
and WORK mode which activates the hydrostatic
drive system that moves the truck at controlled
speeds of 0 to 7 mph for cutting operations and
makes most cutter related functions available for
operation. The PTO on the engine transmission
powers the accessory hydraulic system pump
when activated by the TRUCK PTO switch in the
joystick panel while in WORK mode.
The engine and the chassis transmission were
specified and installed by the chassis manufac -
turer. Refer to the truck chassis operation manual
for additional information on the engine and trans-
mission.
Engine
The chassis engine powers the truck drivetrain
and all cutter systems and components. Typically,
the engine will be operated at maximum full load
RPM during operations. The actual RPM will vary
somewhat, depending on the chassis and selected
options. Operating the engine below the minimum
required RPM will place excess load on the engine,
resulting in poor efficiency and could cause it to
overheat.
Transmission
The chassis is equipped with an automatic trans-
mission. It is essential to select the correct gear
for proper operation while in WORK mode. The
hydrostatic drive and cutting system are designed
to operate with the transmission output shaft
turning the same RPM as the engine or at a 1 to
1 gear ratio. The following outlines the procedure
for selecting the correct gear for WORK mode with
an automatic transmission.
Automatic Transmissions must meet two condi-
tions to provide the proper RPM for the output
shaft. The correct output gear must be selected
and the torque converter must be locked so that
it cannot slip. Normally 4th gear is correct. This
is called 4-4 Lockup.
Automatic Transmission Gear Selector & LED Screen
PTO Switch ON & 4/4 Lockup Displayed
Truck & OMSI PTO Buttons On joystick Panel