Carburetor engine
The mechanical fuel pump is located on the left side of the cylinder block and is driven via an intermediate shaft. To check the fuel pump, it must be removed.
Warning: Fuel may spill when removing the fuel tank. Gasoline and its vapors are toxic and flammable, so ensure good ventilation of the workplace. Avoid contact of fuel with skin. Wear fuel-resistant gloves. No open flames, fire hazard! Have a fire extinguisher ready.
Removal
Disconnect the negative (-) battery cable.
Caution: When the battery is disconnected, the contents of electronic memory devices, such as engine fault codes or radio codes, are erased. Before disconnecting, also read the instructions in the chapter "Removing and installing the battery".
Remove the air filter, see next chapter.
Loosen the clamps and disconnect the fuel lines. Plug the lines with clean bolts of the appropriate diameter. Mark the fuel lines with adhesive tape.
Caution: Before disconnecting the fuel lines, place a rag underneath to collect any spilled fuel.
Note: If the hoses are secured with clamps, they should be cut and replaced with clamps tightened with a screw during assembly.
Unscrew the 2 bolts securing the fuel pump flange and remove the pump together with the seals.
Examination
Move the pump lever. The suction noise should be clearly audible.
By placing your finger on the holes of the fuel line fittings and simultaneously pressing the lever, you can check the presence of suction and discharge at the pump.
At the service station, you can check the pump discharge pressure. The prescribed value is between 0.24 and 0.41 bar.
If the prescribed value is not reached, the pump must be replaced. The pump cannot be repaired.
Installation
Using a scraper, carefully clean the sealing surfaces of the cylinder block, fuel pump and insulator from seal residues.
Install the fuel pump with new sealing gaskets and tighten the mounting bolts to 15 Nm.
Connect the fuel lines in accordance with the marks and secure them with clamps.
Connect the ground (-) cable to the battery.
If available, set the clock and enter the radio theft protection code.
Start the engine and check the tightness of the fuel line connection to the pump.