Moin, I have a problem, and I have installed a Webasto Thermo Top C heater in my 96er 850. Almost everything is ok, only the fuel supply does not work. The dosing pump pumps no fuel for the stationary heating. I have installed the fuel dosing pump as far back as possible after the Webasto instruction (under the vehicle next to the petrol filter). I get the petrol for the dosing pump with the help of a T-piece from the fuel return line, which runs parallel to the supply line. In a test run before installation everything worked out. Did the system ventilate, the two connecting wires swapped and even the pump turned around test by test. Without success. Does the return line possibly have a check valve? Did I accidentally catch the lead line? According to my knowledge, the petrol filter is in the lead and therefore I took the other line. Who has experience with the stationary heating (or another one in which the gasoline also has a pump for the pump). SH is promoted) and can give me tips for connecting the dosing pump? Thank you and thank you very much Ole