There is a really good 3 part video series that walks you through the removal and installation of new injectors: Injector Removal And Installation - Part I. I watched all the videos to make sure I knew what to expect. The video series is very detailed and easy to follow. I highly recommend it. Rather than try to post a whole new set of instructions for the injector removal / installation, I'm simply going to document some reference pictures, as well as the little tricks I used that helped me through the install. I'll periodically make reference to the videos as I go through the process.
Figure 1: Remove the intake horn and grid heater assembly to gain access to the hard fuel lines. Remove the bolts for the APPS sensor, and place it to the side of the engine bay. I'm running a Banks High Ram on my truck, which uses studs to fasten the grid heater and intake horn to the plenum. Your truck will likely have bolts instead of studs, allowing for even greater accessibility.
Figure 2: Remove the valve cover. This is a bit easier said then done. The Cummins block is extremely long, and it often takes some concerted stretching to reach cylinders 5 & 6. The video instructs you to loosen all five bolts, but leave the last two attached to the valve cover. I found this to be a huge PITA. The two remaining bolts either get hung up in the valve train assembly, or become caught in the firewall insulation when trying to guide out the valve cover. I prefer to remove all the bolts which allows the valve cover to easily be removed. Please note that the insulation is friable, so be careful that small pieces do not fall into the valve train assembly while the cover is off.
Figure 3: Using a 19mm wrench, loosen the hard fuel lines from the rear of the VP44, and from cylinders 1,2, and 4. Remove all the brackets that hold the fuel lines to the intake plenum. DO NOT remove the small blue clamps that hold the hard lines together. You should then be able to remove the hard fuel lines for cylinders 1,2, and 4 as an assembly. The video covers this in detail.
Figure 4: If the stock lifting eye bracket connected to the rear of the plenum is still in place, it will need to be removed in order to gain access to the hard fuel lines for cylinders 5 & 6. A breaker bar (pictured below) or socket wrench with a cheater pipe can be used to loosen the lifting eye bracket bolts if they are excessively tight.
Figure 5: Remove the hard fuel lines for cylinders 3,5, and 6. DO NOT remove the small blue clamps that hold the hard lines together. You should then be able to remove the hard fuel lines for cylinders 3,5, and 6 as an assembly.
Figure 6: Gently pry out the connector tubes for all the cylinders (in the image below, the connector tube for cylinder #1 has been removed). A stubby flat blade screwdriver works very well for this. The injector tubes MUST be removed prior to removing the injectors. Failing to do so will likely result in damage to both the injector and connector tube. Please note that very little force is needed to lever out the connector tubes from the head. The connector tubes are highly machined, and require careful handling. Once removed, place the connector tubes on a clean towel in a safe area.
Figure 7: Once all the connector tubes have been removed, use an 8mm socket to remove front bolt for the injector hold down clamp. DO NOT remove the rear bolt, as it it pre-torqued to spec and the hold down clamp is slotted to allow for its removal. Thread one of the valve cover bolts into the top of the injector, and use a large flat blade screwdriver to gently lever out each injector. Repeat this process to remove all the injectors. It is CRITICAL that the copper crush washer on the end of each nozzle comes out with each of the old injectors. If the copper washer does not come out with the old injector, a small hook tool should be used to extract it from the injector hole. Please note that the injectors are simply press fit in place, and minimal effort is needed to lever each one out of the head. Pictured below is the empty cavity where the injector and copper crush washer for cylinder #1 has been removed.
Figure 8: Now it's time to install the new injectors. I recommend that you array the injector, copper crush washer, connector tube, hold down clamp, and bolt for each cylinder. Inspect the O-rings on both the injectors and connector tubes for obvious signs of damage or failure. Use a little oil from the valve train to lightly oil all the injector and connector tube O-rings. Next, perform the installation one cylinder at a time, starting at #6 and working forward to #1.
Figure 9: The injectors require only a small amount of force to be seated into place. Nevertheless, the injectors for cylinders 6 and 5 can still prove to be difficult to seat. I suggest using a hard rubber mallet set on the top of the injector, and a long pry bar. You can then use the underside of the hood as the lever fulcrum to gently seat the injector. Very minimal force is needed, and you should hear an audible click once the injector is seated properly. Make sure the hole in the side of the injector is lined up with the connector tube. The connector tube can then be inserted by hand and pressed into place with one finger. As with the injector, an audible click should be heard when the connector tube is seated properly. Reinstall the injector hold down clamp, making sure it seats properly into the slot in the top of the injector. Torque the hold down bolt to 60 in/lbs. DO NOT over torque.
Final Steps: Now all that's left to do is assemble the parts in the reverse order you took them off. It is important to note that you should completely tighten the hard fuel line into the head for cylinder #2. If you forget to do so and install the intake horn, you will not be able to access the 19mm nut. Beyond that, follow the bleeding process for the fuel lines as described in the video. I made it a point very carefully to bleed the lines of all air. As a reward, it only took 5 seconds of cranking for the truck to start!
Summary: Swapping in new injectors really is easy, and very much in the reach of even a novice mechanic. The important thing to do is put on your patience hat before you begin. The one thing that can potentially create a little frustration is the reaching involved to get to cylinders 5 & 6.
I will say that the new II Dragon Flow's are incredible!! They fuel very aggressively. With the TST box on 2, I can roll enough coal to be worthy of the game Spy Hunter before the turbo starts cleaning up the air/fuel mixture at higher RPM's (I've not yet dared to turn up the box any higher). With the TST box off and running a CaTCHER tune only, the injectors seem to run pretty clean and cool. The truck idles very smoothly with the new sticks (maybe even smoother than stock), and the exhaust note is now slightly lower and burlier. When letting out the clutch, the engine has a legitimate lope (which I've already received some thumbs up for- that's kinda cool! ). So far, I'm pleased with the balance of performance and practicality. Hopefully here in the next week or so I'll be able to schedule a dyno run time to see what the truck will do with everything set to kill.
Edited by 2002Dodge, 24 September 2011 - 05:40 PM.