Webasto Thermo 90, Workshop Manual

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Thermo 90 8 Servicing
805
8.6.2.1 Fuel Tapping
Fuel tapping must be from the fuel reservoir or from a
separate tank (Figs. 803, 804, and 805). This separate
fuel tapping avoids an influence on the pressure.
Fig. 803 Webasto Fuel Tank Tap
* Use fuel tank tap only on metal fuel tanks
Fig. 804 Fuel Tapping from Plastic Tank
(tapping via fuel drain plug)
Fig. 805 Fuel Tapping from Plastic Tank
(tapping via fitting plate)
NOTE
The fitting plate must be made of sheet metal.
Vehicles with Fuel Engines
In combination with carburettor or fuel injection engines
with return line the heater's fuel system integration must
be in the return.
Carburettor engines without return line must have the
heater integrated in the fuel supply between the vehicle's
fuel tank and fuel pump.
NOTE
• A fuel supply line can normally be identified by an
installed fuel filter.
• If an exhalation vessel is installed in the vehicle's
fuel system, fuel tapping must be upstream of the
exhalation vessel.
For fuel tapping from the supply or return line only the
specific Webasto fuel tap, e.g. Ident. No. 470 910 for
Ø 8 mm may be used. The fuel tap must be mounted so
that the air or gas bubbles can escape towards the fuel
tank. Air or gas bubbles may build up in the vehicle fuel
line in case of a leak in the vehicle's carburettor or fuel
pump or when environmental temperatures are higher
than the fuel evaporation temperature.
> 25 mm
25 Hole Pattern
Gasket
Plastic Tank
Gasket
Tank Fitting Plate
Fuel Tank Tap