Installing the Fuel Filter Preheat System

In extreme cold, diesel fuel thickens and clogs the fuel filter. In order for the fuel to remain fluid even at low outside temperatures, it must be preheated. To do this, you need to install a filter with a fan valve. Then the excess fuel, which is usually driven back to the tank by the fuel pump, is sent to the fuel filter. This fuel heats up as it passes through the pump. At temperatures below 0 degrees. The heated fuel is supplied by the fuel pump to the filter. If the temperature of the fuel in the filter rises to over 10 degrees. C, then the blower valve switches and excess fuel enters through the fuel outlet line directly into the tank. Therefore, when using winter diesel fuel, the fuel system remains operational up to a temperature of -25 degrees. WITH.

Installation

Attention! It is necessary to use an additional set of equipment VAG-251 198 127. It is not necessary to install a ball check valve in the fuel outlet line.

Unscrew the fuel lines.

Unscrew the fuel filter from the top.



(23-171) assemble a new filter: put on the O-ring, insert the regulator valve as shown in the figure and fasten with clips.


Install fuel filter with new holder.

Connect fuel lines and secure with clips.

1 - supply pipeline from the fuel tank. When installing, cut off the ring fitting from the existing plastic pipe and push a new hose 7x3x120 mm onto the plastic fuel pipe.

2 - fuel supply line to the fuel pump. Remove the existing transparent pipe. Saw off the annular part from the side of the filter (the connector remains!), strip the connection and clean the pipeline. Push a piece of hose 7x3x120 mm onto a transparent plastic pipeline and secure with a clamp near the remaining connecting fitting. Reinstall the transparent pipeline.

3 - outlet pipe from the fuel pump. Cut off the existing outlet pipe behind the ring fitting. Split the residue at the connecting nipple and remove. Install a new outlet hose 5x3x800 mm.

4 - outlet pipeline to the fuel tank. Put a new piece of hose 7x3x300 mm on the existing cut fuel line. Connect the outlet pipe to the end of the control valve marked with an arrow.

Fasten new fuel hoses so that they do not come into contact with moving parts.

Attention! If the regulator valve breaks during installation, then, although upon completion of the work, the motor starts to work, but the fuel is not sucked in. Then no fuel flows through the transparent pipeline. In this case, a new regulator valve must be installed.