1. Park the vehicle on a level surface and turn off the engine.
2. Locate the fuel filter. It is usually located on the passenger side of the engine, near the fuel tank.
3. Place a drain pan under the fuel filter to catch any spilled fuel.
4. Loosen the fuel line connections on the fuel filter. Use a wrench to loosen the fuel lines. Be careful not to spill any fuel.
5. Remove the fuel filter. It is usually held in place by a bracket or clamp. Use a screwdriver or pliers to remove the bracket or clamp.
6. Install the new fuel filter. Insert the new fuel filter into the bracket or clamp. Hand-tighten the fuel line connections.
7. Tighten the fuel line connections. Use a wrench to tighten the fuel lines until they are snug.
8. Start the engine and check for leaks. Look for any leaks around the fuel filter or fuel lines. If you see any leaks, tighten the fuel line connections until the leaks stop.
Changing the water separator on a 2003 Isuzu NPR diesel:
1. Locate the water separator. It is usually located on the passenger side of the engine, near the fuel filter.
2. Place a drain pan under the water separator to catch any spilled fuel and water.
3. Loosen the drain plug on the water separator. Use a wrench to loosen the drain plug. Allow all fuel and water to drain out.
4. Remove the filter element from the water separator. Use a wrench to loosen the filter housing and remove the filter element. discard the old filter element.
5. Install the new filter element. Insert the new filter element into the water separator housing and hand tighten it.
6. Replace the water separator drain plug. Use a wrench to tighten the drain plug until it is snug.
7. Start the engine and check for leaks. Look for any leaks around the water separator. If you see any leaks, tighten the drain plug or the water separator filter housing until the leaks stop.
