Changing Fuel Filters: 2008 Ford Diesel Edition

Changing the fuel filters on a 2008 Ford Diesel is a straightforward process, but it requires some mechanical knowledge and specific tools. The first step is to gather the necessary parts and tools, including fuel filters, a fuel line disconnect tool, a flat-tip screwdriver, rags, safety glasses, and a 36mm socket. It is recommended to have less than a quarter tank of fuel before starting the process. The next steps involve draining the fuel, removing and replacing the filters, and cycling the key to purge air from the system. It is important to follow the manufacturer's instructions and take safety precautions when performing this task.

Drain the fuel

To drain the fuel from your 2008 Ford Diesel, follow these steps:

Firstly, ensure the truck is level and remove the fuel tank cap. This will help to prevent fuel from spilling out when you start working on the filters. Next, locate the fuel/water separator. This is mounted on the inside of the frame rail, under the driver's side of the truck. You should see a yellow handle—turn this to open the drain and allow the fuel to drain out into a container.

You may want to place a rag over the frame rail to catch any diesel that leaks when you remove the filter cap. You will need a 36mm socket to remove the cap. Once the cap is off, pull out the filter slowly, allowing any remaining fuel to drain back into the separator.

At this point, you can also remove the engine fuel filter, which is located on top of the engine, on the driver's side. Again, use a 36mm socket to remove the cap, and be prepared for more diesel to drain out.

Now, you can replace the O-rings and lubricate them with fuel, before installing the new filters.

Remove the engine fuel filter

To remove the engine fuel filter on a 2008 Ford Diesel, follow these steps:

Firstly, ensure you have the right tools for the job. You will need a 36mm socket and a fuel line disconnect tool. It is also recommended to have a flat-tip screwdriver, rags, and safety glasses.

Now, let's get started on removing the engine fuel filter:

• Park your Ford Diesel on a level surface and remove the fuel tank cap. This will help reduce fuel pressure and minimize leaks when you start working.
• Locate the engine fuel filter. It is usually mounted on the engine or inside the frame rail under the driver's side of the vehicle.
• Place a drain pan or container under the filter to catch any spilling fuel.
• Using the 36mm socket, slowly remove the cap from the engine-mounted filter. Pull the filter out gently, allowing the fuel to drain back into the pan. Be cautious, as diesel fuel can be messy and hazardous.
• Clean the filter cap and mounting area thoroughly. Use a clean rag or brush to remove any debris or residue.
• At this point, you may also need to open the drain on the HFCM (fuel-water separator) to completely drain the fuel from the system. It is usually located under the driver's side, mounted on the frame rail.
• With the filter removed, you should now be able to access the O-rings. Replace them, and lubricate the new ones with a small amount of fuel or clean motor oil.
• Ensure you have new fuel filters ready to install. It is recommended to use OEM (Original Equipment Manufacturer) filters for the best performance and compatibility.

Remember to work cautiously and refer to a qualified mechanic or a detailed guide if you need further assistance. Working on fuel systems can be dangerous, so take your time and prioritize your safety.

Remove the driver-side frame filter

To remove the driver-side frame filter on a 2008 Ford Diesel, follow these steps:

Firstly, ensure the truck is level and remove the fuel tank cap. It is recommended to wait until the fuel level is below 1/4 tank before proceeding, as this will prevent fuel from continuing to drain out once the filter is removed.

Now, locate the filter. The driver-side frame filter is mounted to the inside of the frame on the driver's side. You will need to get under the truck to access it. Once located, place a pan or container underneath the filter to catch any fuel that may spill out during the removal process.

The next step is to relieve the fuel pressure. Allow the truck to sit for a few hours to do this. There may still be some leakage when you remove the filter, but it won't be as much as if you hadn't waited.

Now, you can begin to disconnect the fuel lines from the filter. Start with the fuel line connecting the fuel tank to the filter. There should be an orange clip holding this line in place. Carefully remove this clip with a flat-tip screwdriver, as it is fragile and can break easily. Once the clip is removed, push the fuel line up and out of the way.

Next, disconnect the forward fuel line from the filter. There is a safety clip that must be removed first. Pinch the front portion of the clip to unlock it, then push it back towards the filter and spread it out to free it from the coupling. Remove the clip from the line or move it out of the way.

Now, you can use a fuel line disconnect tool to separate the forward fuel line from the filter. Insert the tool into the coupling and push it away from the filter until the coupling releases. Then, pull the fuel line free with one hand, while catching any excess fuel with a rag in the other.

The filter is now almost free, but you still need to remove it from its bracket. The bracket is very tight, so you may need to use one hand to pull back one side of the bracket while using your other hand to ease the filter out. With the filter removed, you can now clean the mounting area and replace the filter.

Lubricate the plastic threads on the filter caps

Lubricating the plastic threads on the filter caps is an important step in changing the fuel filters on a 2008 Ford Diesel. This step ensures that the caps can be easily removed and reinstalled, and helps to prevent leaks. Here is a detailed guide on how to lubricate the plastic threads:

Before beginning, gather the necessary supplies: clean motor oil or diesel fuel, a rag, and a small brush (an old toothbrush can work well).

• Remove the filter caps: Start by removing the engine-mounted filter cap using a 36mm socket. Pull it out slowly, allowing the fuel to drain back. Next, open the drain on the HFCM (fuel filter housing) mounted on the inside of the frame rail under the driver's side and let it drain into a container. Now, remove the cap from the HFCM using the 36mm socket.
• Clean the filter caps: With the caps removed, thoroughly clean both the filter caps and the mounting areas. This is important to remove any dirt, debris, or old lubricant that may be present. Pay special attention to the plastic threads on the caps, as these areas need to be clean and free of debris before lubricating.
• Lubricate the plastic threads: Once the caps are clean, apply a small amount of clean motor oil or diesel fuel to the plastic threads. Use a small brush or your finger to gently coat the threads evenly. Be careful not to over-lubricate, as this can attract dirt and debris, which can cause issues later on.
• Reinstall the filters and caps: With the threads lubricated, you can now install the new filters into their respective caps. Make sure the filters are properly seated and secured in the caps before reinstalling them onto the truck. Tighten the caps to the specified torque (usually around 20 ft-lbs).
• Prime the fuel system: After tightening the caps, cycle the key in the ignition 6 times for 30 seconds each time without turning on the engine. This process purges air from the fuel system and helps to prevent air locks.

By following these steps, you will ensure that the plastic threads on the filter caps are properly lubricated, making the filter change process smoother and helping to prevent leaks in your 2008 Ford Diesel.

Cycle the key 6-8 times

Cycling the key is an important step in the fuel filter replacement process for Ford diesel engines. It helps to purge air out of the system and ensures that the fuel system is properly primed before starting the engine. Here is a detailed guide on how to approach this step:

Before you begin cycling the key, make sure you have completed the previous steps in the fuel filter replacement process. This includes draining the fuel, removing and replacing the old filters, and tightening the new filters' caps to the specified torque settings. It is also recommended to use a 36mm socket for this task.

Now, for the key cycling:

• Insert the key into the ignition and turn it to the "on" position, but do not start the engine. You will simply be powering up the fuel system without actually turning over the engine.
• Hold the key in the "on" position for approximately 30 seconds. Refer to your specific Ford model's instructions for the exact duration.
• Turn the key back to the "off" position and wait for another 30 seconds or the specified duration.
• Repeat this process for a total of 6 to 8 cycles. Each cycle involves turning the key to the "on" position for a set duration, followed by turning it back to the "off" position for the same duration.
• Listen carefully during the process. You may hear gurgling sounds, which are normal, especially during the first few cycles.
• After completing the specified number of cycles, try to start the engine. It may run a little rough initially but should smooth out quickly.
• If the engine fails to start, you can try cycling the key a few more times. Ensure that the fuel cutoff switch, located on the passenger side of the dashboard, is held down while cranking.

Remember, cycling the key is a crucial step to ensure that air is purged from the fuel system and that the new filters are properly primed. Taking your time with this step can help prevent issues with starting the engine and improve the overall performance of your Ford diesel engine.

Frequently asked questions