Polyethylene Fuel Tank Repair; Steel Fuel Tank (Optional); Steel Fuel Tank Drain Plug - PREVOST H3-41 Maintenance Manual

SECTION 03 : FUEL SYSTEM

5.5 POLYETHYLENE FUEL TANK REPAIR

NOTE
Fuel level must be lower than perforation to
carry out this procedure.
WARNING
Park vehicle safely, apply parking brake, stop
engine and set battery master switches to the
OFF position before working on the vehicle.
1. Locate perforation on fuel tank.
2. If necessary, remove fuel tank as per
instructions in this section.
3. Drill perforation with a 23/64" bit. Make sure
drill hole is perfectly round.
4. Insert a screw (Prevost #500196) and a
washer (Prevost #5001244) into anchor nut
(Prevost #500331).
5. Place assembly in drilled hole. Tighten screw
by 10 complete turns. Refer to Figure 14.
6. Apply sealant on
#507300) and seal hole with the head plug.
FIGURE 14: FUEL TANK REPAIR

5.6 STEEL FUEL TANK (OPTIONAL)

Some X3-45 Commuter coaches may be
equipped with an optional steel fuel tank with a
legal capacity (corresponding to 95% of gross
capacity) of 180 US gallons (681 liters) and 6.3
US gallons of unusable fuel.
The fuel filling access door is located on the R.H.
side of vehicle providing easy fuel filling.
A Level Control Valve (LCV) on the fuel tank
connection panel relieves pressure buildup and
allows offset air in the tank to escape during
filling. A whistle mounted at the LCV outlet can
be heard as air escapes.
LCV will close when the fuel reaches the level in
14
PA1621 Maintenance Manual All Series | Revised May 2018
head plug (Prevost
03014
During fueling, the
the tank corresponding to 95% of the tank
volume, permitting a small build-up of pressure
in the tank. When the back pressure reaches
between 1.1and 1.5 psig it forces the filling
nozzle to close automatically.
FIGURE 15: STEEL FUEL TANK ASSEMBLY
5% of tank inside space is kept filled with air with
no exit opening, allowing for a fuel expansion
safety margin. A drain plug, accessible from
under the vehicle, is fitted at the bottom of the
tank.

5.7 STEEL FUEL TANK DRAIN PLUG

NOTE
For faster emptying, it is recommended to
siphon fuel through the opening left on the
connection panel once the pressure relief valve
is removed.
Apply Loctite 567 Thread Sealant on drain
plug. With any sealant, the first one or two
threads should be left uncovered to avoid
system contamination.