Unscrew the filter from the filter flange by hand. If it is too tight, unscrew the filter with a strap wrench.
If you don't have a strap wrench, unscrew the two bolts at the top of the filter and remove the inlet and outlet fuel lines by squeezing the clamps. Also, disconnect the plug for heating the filter flange. Clamp the flange in a vice.
Fill the filter to the brim with diesel fuel and screw it onto the filter flange by hand.
Caution: Do not overtighten the filter. When the gasket is seated on the filter flange, tighten the filter another 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 technical petroleum jelly to facilitate installation.
The assistant should crank the engine with the starter until fuel begins to flow from the filter. This will quickly remove air from the filter.
Put the fuel line from the injection pump onto the filter. Replace the damaged gasket.
Start the engine. After several engine accelerations, the fuel should flow through the transparent fuel line to the high-pressure fuel pump without bubbles and there should be no leaks.
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