Unscrew the filter by hand from the filter flange. If it is too tight, unscrew the filter with a strap wrench.
If there is no strap wrench, then unscrew the two bolts at the top of the filter and remove the inlet and outlet fuel lines by compressing the brackets. In addition, disconnect the plug for heating the filter flange. Clamp the flange in a vise.
Fill the filter to the brim with diesel fuel and screw onto the filter flange by hand.
Caution: Do not overtighten the filter. When the gasket is seated against the filter flange, tighten the filter an additional ½ turn.
If necessary, install the filter flange together with the filter and connect the plug and fuel supply hose. Replace the damaged gasket and lubricate it with petroleum jelly to facilitate installation.
Have an assistant turn the engine over with the starter until fuel comes out of the filter. In this way, the air will be quickly removed from the filter.
Put the fuel line from the injection pump on the filter. Replace damaged gasket.
Start the engine. After several engine starts, bubble-free fuel should flow through the transparent fuel line to the injection pump and there should be no leaks.