Thank you for your response. Now if I may, I would like bother with a couple more questions.
so does the solenoid sit atop the injector?
Is this why Powerstroke injectors cost $1200?
How reliable is the HPOP and what does it cost to replace?
How long do these injectors and HPOP typically last?
Is this fuel system a bigger PIA than the IDI fuel system?
FatBack,
The
HEUI (Hydraulicaly operated, Electricaly acuated, Unit Injector) Is a one piece unit. From what I have seen, they are maybe 6 or 7 inches tall. At the top is an electrical solenoid that will allow High Pressure Engine Oil to enter the upper part of the injector. This high pressure oil is at ~500PSI at startup an on a 6.0 can go to 4000PSI under a hard load. The chamber fills and at the appropiate timing the solenoid allow the oil to be released agains the intensifier piston, this creates the fuel pressure, the "pop" pressure on the injector is ~3100PSI. This is why that injectors are more expensive. Yes it is true, you can replace all the injectors in an IDI for the price of 1 HEUI injector. However, if you look at a GOOD rebuild, or a Moose Product + Injectors and a return like kit, you are fairly close in price. The stock HPOP I have read is around $500.
The HPOP and Injectors are typically very reliable, however, they are very sensitive to fuel and oil quality. DO NOT run "junk" fuel in a 6.0 and newer. I personally would not in any HEUI system, but there are members that have run alternate fuels in the 7.3 with some success. These do not have an "expected service life" like the IP and Injectors on an IDI have. I have heard of stories of trucks that are stock, and well maintained that have 400+k miles on the original HPOP and HEUI Imjectors. But well maintained is the key!!!!
On the complexity, all the fuel supply and returns in a 6.0 and newer (not sure on the 7.3) are all passages in the head. So if you replace an injector, that is all you replace, however, the injectors are located under the Valve Covers, and on the 7.3 so are the GP's. so you have to remove the valve covers to replace the injectors, but you do not have the supply and return lines to deal with. So it may seem more complex, however, each system has its own quirks and complexities.....
I hope this helps. If you look at the entire "book" that I linked to a page in, that is called the "6.0L Bible" and has a lot of good info on hew things work and where they are located.....
