Monaco Camelot 2007, Руководство пользователя

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Section 10 — cHaSSiS information
camelot 2007
NOTE
Always carry an extra filter as one tank
full of excessively contaminated diesel
fuel can plug a filter.
To Drain the Filter:
Wear safety goggles.
Shut off the engine.
Open the drain valve, by hand,
counterclockwise approximately 1 1/2
to 2 turns until draining occurs. Drain
water/fuel into a container and dispose of
in accordance with local environmental
regulations.
Close the drain valve by turning
clockwise when clear fuel is visible.
Priming the Engine:
Fill tank with 30 gallons of fuel or more
if parked on a slant.
Turn key to on for approximately 30
seconds and then off again. This may
need to be repeated several times before
the system is purged of air.
If unable to start, contact nearest
Cummins Center or phone 1-800-343-
7357 for Cummins Customer Assistance
Center.
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HyDraulIc SyStem
The motorhome uses an engine driven
hydraulic pump to operate both the power
steering system and the engine hydraulic cooling
fan system. The hydraulic pump is a dual stage
pump that uses one half of the pump to supply
pressurized hydraulic fluid to the power steering.
The other half of the pump supplies the engine
cooling fan motors. The hydraulic system uses
the same fluid for both systems, sharing one
common reservoir. The hydraulic fluid used is
an automatic transmission fluid (Dexron III®)
which has a wide ambient temperature operating
range.
Hydraulic fluid passing through the system
also goes through an air-to-fluid cooler mounted
on the outside of the charge air cooler, as well
as a filter. Maintenance requirements for this
system include fluid level checks, filter and fluid
replacement, and inspection.
Hydraulic Pump
The hydraulic pump creates pressure by
meshing sets of gears together inside a close
tolerance housing. A filtered supply of hydraulic
fluid from the hydraulic reservoir enters the
intake side of the pump. The meshing gear
assembly “squeezes” oil through the pump to
the output side, delivering the pressurized fluid
to the power steering gear and the switching
valve of the engine cooling system. Each half
of the pump is equipped with an internal bypass
pressure relief spring. If the hydraulic pressure
should exceed the specified pressure limit, the
internal bypass relief valve will be forced open
to keep the hydraulic fluid at operating pressure.
The hydraulic pressure generally is not rated
in psi but is rated in the term bar. One bar is
equivalent to approximately 14.5 psi. Hydraulic
system pressures with a system at no load may
be as low as eight bars on the output side of
the pump. This is due to the hydraulic fluid
flow of the pump. When a load is placed on the
hydraulic pump, such as turning the steering
wheel, hydraulic fluid flow slows from hydraulic
fluid restriction and pressure increases.
This may be understood as a faucet with
a garden hose attached. Crimping the hose
with the faucet on creates pressure from the
restriction. This principle applies to the hydraulic
system. The hydraulic pump is the supply, the
load is the power steering gear or the hydraulic
fan motors. Hydraulic system pressure at full
load can exceed 130 bar or 2000 psi. Hydraulic
system pressure falls dramatically after the load.
The return line pressure may be as low as six to
eight bars. The fluid enters the hydraulic cooler
where the heat is dissipated.
Hydraulic Cooler
The hydraulic cooler is an important part in the
hydraulic system. This helps keep the hydraulic
fluid from overheating. When a load is placed
on the hydraulic system, heat is created in the
fluid. The hydraulic pump builds pressure that
creates heat in the fluid. Restriction from the
loads applied also creates heat. This heat must
be dissipated to keep the hydraulic fluid from
overheating and breaking down. After cooling,
the fluid is filtered before returning to the
reservoir.