Changing The Fuel Filter On A 24-Valve Cummins Engine

Changing the fuel filter on a 24-valve Cummins engine is a straightforward process that can be done in a few simple steps. This procedure is an essential aspect of diesel engine maintenance, which also includes oil changes, cleaning or changing the air filter, and valve lash adjustments. While the specific steps may vary slightly depending on the make and model of your vehicle, the basic process typically involves draining the fuel from the canister, removing the old filter, inserting a new filter, and refilling the canister with clean fuel. It is also important to replace any gaskets or O-rings and to prime the new filter before starting the engine.

Drain fuel from the canister

To drain the fuel from the canister of a 24-valve Cummins, first, get yourself into a position that looks like you're hugging the brake master cylinder. Place a small drip pan under the filter to collect the fuel. You only need to drain a small amount of fuel to prevent spillage when you remove the filter. To do this, simply unscrew the WIF (Water in Fuel) sensor. Once you've drained a small amount of fuel, close the WIF sensor. Now, you can proceed to remove the filter.

If you're working on a 1997-1998 24-valve Cummins, it is recommended to open the water drain on the fuel filter canister for a few seconds to drain the fuel level below the top. This will make the process of removing the filter cartridge much cleaner and easier.

For a 2001 24V 5.9 Cummins, the process is a little different. You will need to drain all the fuel from the filter housing. Close the drain valve and remove the drain hose from the housing. Place a plastic bag under the filter area to catch any drips. Loosen the nut on the top of the filter housing until the bottom housing is free. Make sure to hold the bottom of the filter housing to prevent residual fuel from spilling out.

Now that you've drained the fuel from the canister, you can proceed to the next steps of changing the fuel filter.

Remove the canister bottom and old filter

To remove the canister bottom and old filter, first, place a can under the fuel filter drain hose. Drain all the fuel from the filter housing. Close the drain valve and remove the drain hose from the housing. Loosen the nut on top of the filter housing until the bottom housing is free. Make sure to hold the bottom of the filter housing, or it will drop and spill. When the lower housing is free, lower and remove it from the top housing.

Remove the filter element from the housing, noting the location of the O-rings. If you plan to reuse the O-rings, lubricate them before reinstalling the new filter.

Insert a new filter and fill the canister with clean fuel

Inserting a new filter is a simple process, but it must be done carefully to avoid spillage. First, you will need to obtain a new fuel filter, as well as new o-rings. It is important to lubricate the o-rings before installing them; you can use diesel fuel for this. Next, carefully sneak the new filter back through the wires, ensuring that it is empty. Rest the new filter in the space between the throttle linkage, starter, and throttle cable.

Now, you can begin to fill the canister with clean fuel. Using a funnel with a twist shut-off and a long clear tube, fill the funnel with fuel and run the tube through the fuel lines down to the filter. Then, slowly twist the valve open and start filling the filter. If you fill the filter to the top, there shouldn't be any issues with air in the lines. Once the filter is full, carefully lift it up and screw it back into the housing.

It is important to note that the o-rings swell when exposed to fuel, so be sure to use new o-rings when installing the new filter. This will ensure that you can reliably reassemble the filter canister.

Reattach the canister bottom to the top

Reattaching the canister bottom to the top is a crucial step in changing the fuel filter on a 24-valve Cummins engine. Here is a detailed guide on how to do this:

• Hold the canister bottom in place: When you separate the canister bottom from the top, carefully hold the bottom section to prevent any residual fuel from spilling. This can be done by gently grasping the canister bottom with one hand while loosening the nut that secures it to the top section.
• Align the canister bottom: Once the canister bottom is free, carefully lower and remove it from the top housing. Take note of the orientation and alignment of the bottom section in relation to the top housing to ensure proper reassembly.
• Replace the nut: After inserting a new fuel filter and ensuring all components are clean and in good condition, it's time to reattach the canister bottom. Align the bottom section with the top housing, making sure that the two parts are properly aligned and seated together. Then, replace the nut that secures the canister bottom to the top.
• Tighten the nut: Tighten the nut securely, using the specified torque value provided by the manufacturer or a dealer. This will ensure a proper seal and prevent fuel leaks. The recommended torque value is typically around 15-20 ft-lbs, but it's always best to refer to the official specifications for your specific Cummins engine.

By following these steps, you will successfully reattach the canister bottom to the top of the fuel filter housing on your 24-valve Cummins engine. Remember to refer to the manufacturer's instructions or a trusted repair guide for additional information and torque specifications specific to your vehicle.

Prime the filter by turning the ignition to 'Start' briefly

To prime the filter, turn the ignition to the "Start" position briefly, then back to "Run". The electric lift pump will run for about 20 seconds. Repeat this process once, then try to start the engine. If it doesn't start after 10-15 seconds of cranking, repeat the priming procedure again.

To ensure the fuel canister is adequately purged, turn the key to the "On" position and listen for the mechanical pump in the fuel tank to engage. Then, turn the key enough to engage the starter. Repeat this process four to five times to allow the fuel line to pressurise.

If you have drained the fuel canister during the filter change, you will need to refill it with fuel. To do this, "bump" the key from "On" to "Start" and then back to "On". This will cause the lift pump to run for about 25 seconds. If the canister was completely drained, you should do two or three cycles. Then, you can start the engine normally.

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