PREVOST X3-45 Multiplex, Руководство по обслуживанию

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Section 03: FUEL SYSTEM
PA1562
5
5. Screw bowl onto new filter cartridge snugly
by hand.
CAUTION
Do not use tool to tighten. Tighten by hand
only.
6. Lubricate filter seal with clean diesel fuel or
motor oil.
7. Fill filter cartridge with clean diesel fuel and
attach onto cover. Handtighten an additional
1/3 to 1/2 turn after making full seal contact.
8. Open shut-off valves of the engine fuel
supply line.
9. Run the engine and check for leaks.
CAUTION
If the fuel/water separator continuously
requires draining, it is possible that water or
sediment has accumulated in the fuel tank.
To correct this situation, open the drain plug
under the tank when the fuel gauge indicates
tank is 1/4 full in order to drain any
contaminant.
1.5 SPIN-ON TYPE FUEL FILTER SERVICING
(PRIMARY & SECONDARY)
The primary and secondary fuel filters are
located on the R.H. side of the engine. The
primary filter is located below the starter, and the
secondary fuel filter is below the air compressor.
The threaded sleeves that accept the filters
body are different sizes to prevent mismatching.
Primary filter thread is 1” X 12 while secondary
is 13/16” X 12. The word “primary” or
“secondary” is cast onto the top of the
respective adaptor.
NOTE
The fuel filter adaptors are mounted to the
engine block with two bolts each. Torque
these bolts to 43-54 lbf•ft (58-73 N•m).
A method of determining when filters are
clogged to the extent that they should be
changed is based on the fuel pressure at the
cylinder head fuel inlet fitting and the inlet
restriction at the fuel pump. In a clean system,
the maximum pump-inlet restriction should not
exceed 6 inches of mercury (20.3 kPa) and must
not exceed 12 inches of mercury (41 kPa) with a
dirty system.
At normal operating speeds and with the
standard fuel pressure regulator, the fuel
pressure at the cylinder head inlet is 58-72 psi
(400-50 kPa). Change the fuel filters whenever
the inlet restriction at the fuel pump reaches 12
inches of mercury (41 kPa) at normal operating
speeds. Also, change whenever the fuel
pressure at the cylinder head inlet fitting falls to
the minimum fuel pressure given above.
MAINTENANCE
The primary and secondary fuel filters are of a
spin-on type and must be replaced every
12,500 miles (20 000 km) or once a year,
whichever comes first. If the primary fuel filter
is a fuel filter/water separator type, it is
equipped with a positive seal drain-valve to
prevent water infiltration in engine fuel system.
To drain, loosen positive seal drain-valve below
filter and tighten after water has been flushed
out.
Change the filter cartridge(s) as follows:
NOTE
Use a suitable band wrench or filter wrench,
such as J22775, to remove the filters.
1. Stop engine, place a suitable container
under the filter.
2. Close the secondary and primary filter shut-
off valve (for valve location, See paragraph
1.2. FUEL VALVES").
3. Using a band filter wrench, unscrew and
discard filters.
4. Fill new filter cartridge(s) with clean fuel oil.
Apply a thin coat of clean fuel oil on gasket.
5. Install new filters. Tighten until filter is snug
against the gasket, with no side movement.
Rotate an additional ½ turn by hand.
CAUTION
Mechanical tightening of the fuel filters is not
recommended and may result in seal and/or
cartridge damage. Tighten the fuel filters by
hand only.
6. Open engine fuel supply line shut-off valves.