Fuel pump and filters

Fuel pump replacement

The procedure for replacing the fuel pump is simple and does not require much explanation. The pump is mounted on the head of the block and the air filter must be removed to gain access to it. The pump mounting bolts are equipped with heads with an internal hexagon.

Air filter replacement

The air filter element is made of paper and cannot be cleaned. The flow of air flow through the filter depends on the temperature and load of the engine. The appearance of filters may differ in different types of engines, but they all have the same principle of operation. The air filter with the cover removed is shown in fig. 155. This figure shows the temperature sensor 1, the thermostat in the inlet air duct 2 and the thermostat 3. The temperature sensor has two fittings, one of which has an internal thread and serves to connect the air duct coming from the thermostat.



The operation of the thermostat that controls the supply of cold air can be checked by removing the air duct connecting the back wall of the filter with the vacuum chamber, and then blowing in and pulling air through the mouth. In this case, the damper should open and close, making a clearly distinguishable sound.


For further verification, you can remove the duct with a thermostat. At an ambient temperature of 20°C, the damper should be open no more than 2/3. Otherwise, the thermostat must be replaced.



The filter element should be replaced every 30,000 km, while thoroughly cleaning the inside of the filter housing. On very dusty roads, replace the filter element more frequently. To replace the filter element, release the 5 spring clips and remove the cover. To remove the filter assembly, unscrew the mounting bolts. Close the carburetor inlet with a rag. Between the filter housing and the carburetor there is a gasket that must not be moved during filter installation.