Vehicles With Diesel Engines; Fuel Lines - Webasto Air Top Evo 40 Installation & Operation Manual

Air Top Evo 40/55
If the fuel pump is located inside the tank, fuel can only be extracted from the return line using the Webasto fuel
extractor (see Figure 13), in which case it must be ensured that the return line continues almost to the bottom of the
tank (see Figure 12 for details of the minimum distance from the bottom of the tank). If this is not the case Webasto
fuel extractors or standpipes (see Figures 12, 15 and 16) may be used.
If the fuel pump is installed outside the tank, the fuel connection may also be made between the tank and the fuel
pump, again using only the Webasto fuel extractor (see Figure 13).
6.3

Vehicles with Diesel Engines

The fuel must be taken from the vehicle fuel tank or from a separate tank (see Figs. 12, 15 and 16). This separate fuel
pickup precludes any effect of pressure.
NOTE:
The tank fitting must be made from metal!
6.4

Fuel Lines

Only steel, copper and plastic lines of plasticized, light and temperature-stabilized PA 11 or PA 12 (e.g. Mecanyl RWTL)
pursuant to DIN 73378 may be used for the fuel lines.
Since the lines normally cannot be routed with a constant rising gradient, the internal diameter must not be allowed to
exceed a certain size. Air or gas bubbles will accumulate in lines with an internal diameter of more than 2 mm and
these will cause malfunctions whilst the heater is operating if the lines sag or are routed downwards. The diameters
specified in Figure 11will ensure that bubbles do not form.
The lines should not be routed downwards from the metering pump to the heater.
Unsupported fuel lines must be secured to prevent them from sagging. They must be installed in such a way that they
cannot be damaged by flying road debris and high temperatures (exhaust line).
The fuel lines must be secure at the connections using hose clamps to prevent their slipping.
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Fuel Supply