Installing a fuel filter preheating system (VW Transporter T3)

In extreme cold, diesel fuel thickens and clogs the fuel filter. To keep the fuel fluid even at low outside temperatures, it must be preheated. To do this, 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 is heated as it passes through the pump. At temperatures below 0 degrees C, the heated fuel is fed to the filter by the fuel pump. If the fuel temperature in the filter rises to over 10 degrees C, the fan valve switches, and the excess fuel goes through the fuel outlet line directly into the tank. Therefore, when using winter diesel fuel, the fuel system remains operational down to a temperature of -25 degrees C.

Installation

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

Unscrew the fuel lines.

Unscrew the fuel filter with the upper part.



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

The article is posted on the portal www.vwmanual.ru



Install the fuel filter with a new holder.

Connect the fuel lines and secure with clamps.

1 — feed line from the fuel tank. When installing, cut off the ring fitting from the existing plastic line and push the new 7x3x120 mm hose onto the plastic fuel line.

2 — fuel supply line to the fuel pump. Remove the existing transparent pipeline. Cut off the ring part on the filter side (the connecting nipple remains!), clean the connection and clean the pipeline. Slide a piece of hose 7x3x120 mm onto the transparent plastic pipeline and secure it with a clamp near the remaining connecting nipple. Reinstall the transparent pipeline.

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

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

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

Attention! If the regulator valve breaks during installation, then, although the engine starts to work after the work is completed, the fuel is not sucked in. Then the fuel does not flow through the transparent pipeline. In this case, you need to install a new regulator valve.