Loosen the bolt (2) under the filter by hand a few turns. If it does not unscrew, you can use a clamp, placing pieces of leather or paper under its jaws.
Drain about 200 cm³ of water until clean diesel fuel flows out. Tighten the water drain valve (bolt) by hand.
Remove the fuel line going to the injection pump from the top of the filter by pressing the wire fastener. Have an assistant crank the engine with the starter until fuel starts to come out of the fuel filter, then turn off the starter. This will quickly remove air from the filter.
Caution: Collect any leaking diesel fuel in a suitable container.
Put on the fuel line, replace the damaged gasket, lubricating it with Vaseline to facilitate installation. Start the engine. After several accelerations of the engine, the fuel without bubbles should flow through the transparent fuel line to the high-pressure fuel pump and there should be no leaks.
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