Installation of the ITP Regulated Fuel System for the 7.3L Powerstroke

When Ford introduced their Super Duty line of diesel trucks back in the winter of 1998, they had the great idea of deadheading the fuel rails. In a normal fuel feed situation, the fuel enters the engine, makes a complete loop through the engine, then exits back into the tank. But the Ford engineers had a better plan...so they thought. They fed the fuel into the fuel bowl, then from there pushed the fuel down dead ended fuel rails in the heads. While this may have seemed like a good idea at the time, it didn't take long to realize that if air or crappy fuel got introduced into the fuel system, the only way it was going to escape was through the injectors. There was no other escape route. And, the dreaded cackle began to rear its ugly head. So what is cackle? To make an extremely long story short, its the result of the #6 injector taking fuel away from the #8 injector...which is the last one on the drivers side. This "knocking" or "chattering" was noticeable under load. Fords fix for this was the dreaded "Long Lead" injector which could only be installed in the #8 cylinder hole. The long-lead injector has a longer primary or initial shot of fuel to compensate for the under fueling condition cause by #6.  Sometimes this worked...most times it didn't.

The ITP Regulated Fuel kit helps to solve this issue. In the kit, you are supplied the necessary hardware, lines and fuel pressure gauge to turn the 7.3L dead ended fuel rails into a complete circular fuel feed system. This allows air and foamy diesel fuel to be returned back to the fuel tank, instead of being dumped through the injectors.

To begin the disassembly, first disconnect both batteries. You are going to be exposing diesel fuel to the air, which is flammable. Plus...it prevent you from shorting out something you really shouldn't. Then remove the intake tubing to the turbo and remove the CAC tubes, both hot and cold. Once that is done, in the ITP instructions it mentions to unbolt and move aside the A/C compressor along with the alternator. For this particular project, we were installing a dual hpop system. We discovered that with the hpop reservoir removed, we had easy access to the needed test ports. That is also why in some of the pictures the "Y" intake pipe is also off. For the installation of the regulated fuel system alone, one does not need to remove the "Y" intake pipe. First off, drain out any fuel remaining within the fuel bowl. Once that is done, remove the drivers side inlet/return lines from the fuel bowl, and remove the passenger side head feed lines. Then disconnect the the fuel heater plug along with the fuel drain line on the back of the filter bowl. Now its time to drain the reservoir with some sort of suction device. Remove the allen headed plug on top of the hpop, and draw the oil out. You will then need to remove the exhaust back pressure sensor located on the front of the pump, along with removing the 2 bolts at the bottom that hold the fuel bowl assembly. Once these two bolts are out, you can carefully take out the fuel bowl assembly. Set it to the side to work on later. Once that is completed, there are 4 bolts that hold the reservoir to the pump gear. Loosen these and carefully remove the pump. You now have complete access to the test ports located behind the A/C compressor and the alternator.  Now that you have access to everything, you need to remove the factory fuel feed lines. The drivers side line is connected to the check valve behind the alternator bracket. *Note - in the above picture to the right, that line is a new line from ITP. The arrow is pointing to the location of the drivers side check valve* You will need a 9/16" wrench for this. The passenger side line runs to the rear of the head, next to the downpipe. The passenger side line also has a clamp holding it in place in the middle of the head. You need to remove that as well. Once you have the lines out, set them safely aside. You will not be using them again. Since the next step is going to be access the fuel rails themselves, its a good time to wipe down and clean around the check valves themselves, located at the drivers side front behind the alternator, and the passenger side rear by the down pipe. You may also want to clean around the test ports that will be accessed. The drivers side is on the rear of the head by the drivers side turbo up pipe. The passenger side test port is located behind the A/C compressor. This might also be a good time to squirt a little penetrating oil  around the test port plugs as they can be a little difficult to remove. Now you need to remove the check valves. These check valves have a very small little screen in them. When I removed my check valves, I found some gasket debris located in the screen. Since this is post filter, it appears like the debris is from the junky plastic gaskets that ford used on the supply line. The ITP kit supplies much better feed line gaskets so removing the screens was not a concern. After the check valves are out, you can remove the test port plugs. Your best bet to remove these would be a 9/32" 4-point socket. If that's not available, a 5/16" or 8mm wrench will work, just be careful not to round off the corners. The step in the disassembly process is to remove the 2 fittings from the passenger side outlets of the fuel filter bowl. Set aside as they will no longer be used. Everything has now been removed, and its time to start putting things together.

Assembly

There are a couple of important things to keep in mind before you begin to put everything back together. Several of the fittings that are used are 1/8" NPT fittings. These require a small amount of Teflon tape...key word here is SMALL. All you need is one to two layers maximum. And be sure to use Diesel/Fuel/Oil compatible Teflon tape. This tape comes in a yellow container, not your typical white container. Finally, keep in mind that the test ports you accessed are not chamfered. Be patient in trying to get the new fittings in. You do not want to cross thread these.

The test port plug at the rear of the drivers side head is very close to the turbo flange. The ITP kit give you two choices for installation here. There is a 1-piece steel fitting, or a 2-piece brass fitting. For me...the two piece brass fitting was better, and even then I had to take a file and file down a little big of the edges. In the last picture you can see how its mounted in the head, making sure that it points straight up. You can now also install the fitting that goes into the passenger side test port, located at the front of the head. You now also need to install the fittings into the ports on the cylinder heads where the factory check valves were located. This was the drivers side front and the passenger side rear. You are now ready to begin installing fittings into the fuel bowl. The fuel bowl is very susceptible to cracking if the fittings are over tightened...so be gentle here. If you crack the fuel bowl, you will need to replace it before going any farther. Install one of the "1/8" NPT to #4 JIC 90° fittings onto the front port of the fuel bowl. This fitting will have a 45 degree angle and point toward the rear of the bowl when tight. Install the other "1/8" NPT to #4 JIC 90° fitting onto the rear port. This fitting will point straight back when tightened. Now you need to remove the factory fuel pressure regulator located on the drivers side of the fuel filter bowl. Be careful not to lose the o-ring and screws, as they will be needed a bit later on. Find the 60Vl-6 VibraLok sleeve. This sleeve replaces the used sleeve on the end of the factory feed line, which is the lower line on the drivers side of the filter bowl. You may need to lightly spread some diesel fuel or light oil to work the sleeve over the end of the flared tube. And trust me here, they are difficult to find if dropped. Do the same with the 60VL-5 sleeve located directly above that line. Now install the ITP return fitting using the factory o-ring and screws from the factory pressure regulator. The ITP should face up and forward. Do not overtighten the Torx screws. You can now place the fuel filter bowl back into the truck. Don't bolt into place just yet though. Now its time to connect the fuel lines. Start with the passenger side line. Route the line as shown and connect to the lower fitting on the passenger side of the fuel bowl. Now do the same for the drivers side line. The hose should make a gentle bend around the back of the filter bowl and attach to the upper fitting. Once you have the fuel lines connected...replace the hpop reservoir, then re-install the fuel filter retaining bolts. Once that is done, you can reconnect the filter bowl drain line along with the fuel heater and the exhaust backpressure sensor.   You can now connect the stock fuel return line to the newly installed ITP return fitting. With the ITP return fitting being aluminum, be extra careful not to cross thread the nut or damage to the threads may occur. Also of note...if the return line is inserted too far into the fitting, it can cover the return port from the regulator and cause higher than desired fuel pressures.  Now it's time to get the actual regulator set up. Begin by removing the retaining bolt from the Wastegate Control Solenoid bracket located on the front of the intake "Y" manifold. Set the bolt aside, you will need it in a bit, and allow the solenoid to hang so the side. Locate the supplied new regulator mounting bracket and the Aeromotive Fuel Pressure Regulator. Attach the regulator to the new bracket using the supplied screws. Install the bracket/regulator assembly back onto the intake "Y" manifold. Using the supplied M6-1.0x16mm flange bolt, secure the bracket onto the "Y" manifold. Re-install the wastegate control solenoid onto the ITP mounting bracket. The wastegate solenoid will be rotated 90 degrees from its original position. You may have to adjust the red and green lines...but they will reach the new position of the solenoid. Locate the DS-Return line assembly. Connect the SS end of the line to the fitting installed in the rear port on the drivers side head. The line will be routed along the valve cover, and "tweaking" of the line may be needed to prevent rubbing against the valve cover or cylinder head. Connect the hose end to the driver side fitting on the pressure regulator and tighten both ends of the line. Locate the PS-Return line assembly. Connect one end of the hose to the cylinder head fitting, and connect the other end of the hose to the passenger side port on the fuel pressure regulator. Before tightening, make sure there is no interference from other components. One more hose to go. Now locate the RTN-line assembly. Connect one end to the ITP return fitting located on the drivers side of the fuel bowl, and the other to the fitting on the bottom of the fuel pressure regulator assembly. Note that the fitting on the bottom of the fuel pressure regulator was intentionally left loose. Once the return line has been attached at both ends, the 90 degree fitting will position itself for the least amount of tension in the line. Be sure to use 2 wrenches to tighten the jamb nut onto the 90 degree fitting. When all done, it should look like this. Double check each connection one last time to ensure they were properly tightened. Reconnect the batteries, and turn the ignition key to the ON position *DO NOT START* This is to allow the fuel pump to cycle, and allow you to check for leaks. You may need to cycle the key several times, as the pump will only run for about 20 seconds at a time. Once you have determined that there are no leaks, set the base fuel pressure at 65psi. You do this by turning the key to ON again, and loosening the jamb nut on top of the regulator, the rotating the stud clockwise to increase the fuel pressure. . Once you have that done, its time to re-install the serpentine belt, intercooler tubes and anything else that you took off for this project. Lastly, locate the 6' of poly Blowdown line, Push one end of the line onto the nipple on the drivers side of the pressure regulator, and route the other line down underneath the truck, keeping it away from sources of heat and moving parts. This line directs fuel to the ground in the event the diaphragm in the fuel pressure regulator fails. Double check one more time for any leakage. When making the final fuel pressure adjustment with the engine at operating temperature. My best results are right at 65 psi...although the best range seems to be 62 to 68 psi. You may need to increase your fuel filter service intervals because of the increased fuel flow across the filter. Or...you can install an aftermarket fuel filter kit to aid in filtering the increased fuel flow.