does the LBZ have a injector pump and is It mechanical or eletrical and where is It.:confuzeld
I presume you're talking about installing an electric fuel pump somewhere in the fuel supply line between the tank and the fuel filter assembly. This would presumably increase the fuel pressure on the suction side of the pump. However, since the "CP3" is a mechanical pump driven by the cam gear, so its rpm is proportional to engine speed, its lifespan would be a function of engine hours/engine speed. You must believe that the "lift pump" reduces the workload of the CP3 thereby extending the lifespan. I don't understand how raising the pressure on the inlet side will affect lifespan of the mechanical pump. Unless of course, cavitation occurs at the pump somehow causing a momentary loss of lubricity from momentary fuel flow interruption.Technically it is known as a CP3. On the LBZ there is no longer a "lift pump" which pushes fuel up to the injection pump, instead the CP3 does all the work of drawing fuel from the tank and then increasing the pressure to the common rail - it does a lot of work. If you are standing in front of your truck look behind the oil fill tube, you can see where the feed lines coming from the "common rail" disappear into the valley, they end at the IP. Installing a simple 12V lift pump will help your CP3 live a longer and happier life and assist with the dreaded P0087 code.
Great explanation. According to Kennedy Diesel (and I believe him) with a lift pump your fuel filter always stays completely full whereas without one it doesn't always. If you don't believe it cut your fuel filter open and see if the contamination is uniform. Even if the lift pump doesn't help anything live longer it sure makes for easier fuel filter changes:thumb:I don't think the lift pump increases the pressure at the CP3 as most lift pumps run around 12 - 14 psi, however it does reduce the work load on the CP3. Given the CP3 has to suck fuel from the tank, through the filter and into the high pressure side of the system, probably 16 or so feet worth of line on a crew cab the opportunity for cavitation is probably much higher. I can't remember the exact distance but there is a physical limitation of just how far a liquid can be drawn up, (30 something feet I think) due to the effect of gravity and pressure drop, therefore it is harder to draw or suck a liquid a longer distance, add in a fuel filter and the laws of physics begin to apply. Now on the other hand, one can push a liquid an indefinite distance, and through any obstacle with enough pressure - think water jet - which would be the function of a lift pump. So yes, perhaps the CP3 experiences loss in lubrication as a result, or it just does not get enough fuel as the delivery rate is reduced as the pump begins to wear from normal operation, either way around 200,000 towing miles and most CP3's are showing their age, mine was there at 175,000 miles - I would get a P0087 under load frequently. After a bunch of research I installed a lift pump and got to 300,000 miles before it was time for a new CP3 - just my personal experience.
Do a search, youll find hundreds of threads on the subject. Most use Kennedy or Air Dog.Thanks for your thoughts on the matter. To your knowledge, what kind of pump are most people using and where in the system do they typically install it? What circuit do they tap into to power it?
Huh? How does it make it easier? Or do you mean you don't have to pump the filter to get the air out because the lift pump is displacing air with fuel?edit . . . Even if the lift pump doesn't help anything live longer it sure makes for easier fuel filter changes:thumb: