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I just bought my truck 1 1/2 years ago and have a simple question. Since these trucks have a dead end fuel system from the factory, do they come with a LL injector in the two end cylinders from the factory(8 and not sure the #on the other side). The reason I am asking is the truck seems to be getting a little louder each month and I am thinking since I did the ITP reg return that I need to change the LL's out. Thanks
There's only one LL injector, and it's on #8. The passenger's side fuel rail is not a dead end setup like the driver's side. However, I can't remember if the 99's came with the LL or not.
Only in the #8 hole, and your 99.5 may not have one at all unless it was at the dealer for "cackle".
From the "cackle" TSB 03-21-39:
"Some vehicles equipped with a 7.3L Powerstroke diesel engine with engine serial number 661894 through 1311240, may exhibit a noise above the normal sound of the diesel combustion. This noise may sound like a rod knock, but it is intermittent and increases in intensity as the engine warms up to operating temperature. This "cackle" noise may by caused by pressure variation within the fuel rail and in virtually all instances is attributed to cylinder #8 (driver side rear). The "cackle" noise does not cause damage the engine, or impact the engine's performance or economy.
Engines after serial number 1311240 were built with a long lead injector in cylinder #8 and correct calibration from the factory. It is possible for engines with the long lead injector, from the factory or installed in service, to exhibit a "lifter noise" (the long lead injector can be identified by the "LL" stamp on top of the solenoid.) This noise is typically most noticeable when the vehicle is parked next to a brick or concrete wall, such as at a fast food drive through. This noise is a normal characteristic of the long lead injector and is not a reason to replace the injector."
There's only one LL injector, and it's on #8. The passenger's side fuel rail is not a dead end setup like the driver's side. However, I can't remember if the 99's came with the LL or not.
I thought both sides are a dead head not just the drivers side. My understanding is that the number 6 fires just before the number 8 on the drivers side and this is why Ford put in a LL injector in number 8. Having the injector just up stream firing causes a loss of pressure just when number 8 is ready to fire.
I'm of no help in this thread, but I was wondering if anyone could explain what an "LL" injector is, and what it does?
The #6 and #8 cylinder set next to each other at the back of the driver's side bank and also are in the firing order in succession, #6 then #8. Ford's design for the Fuel system also put them at the end of the fuel gallery that is fed from the front of the block, so when they fire the #8 injector is a little short on fuel. Stock injectors are split shot, that is they fire two injection events of fuel each power stroke, and the AE or "long lead" injector fires a larger pilot injection in the split shot to try to make up for the fuel deficiency.
I'm of no help in this thread, but I was wondering if anyone could explain what an "LL" injector is, and what it does?
The newer, and I use that term loosely, split shot injectors use a two injection event per injection as opposed to a single injection in the older single shot. Basically this was to quiet down the diesel injection among other things.
So there is a machined portion of the split shot injector that would bleed of oil pressure momentarily, suspending fuel injection, then the rest of the shot would go.