fuel problem?
- Thread starter riley19d
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well i flushed the entire system, new fuel, bug treatment, and purged the system!NO CHANGE! following that i called the dealership and they think its the injector pump hopefully not, i removed the injectors and they were extremely dirty and caked with carbon so i took them apart soaked them and cleaned them up i put them back as close as i could to the same sitting, still no change so i took the caps off the injectors and loosened them up and tried again still nothing, took the caps back off and tightened them down, still no change, it is still starving for fuel, if i pump the primer it still runs fine but then it dies back down to an idle again so still no luck, i am convinced now that it is either the injectors or the injector pump. What is the adjustment for the injectors?
Rich Waugh
Platinum Member
YOU don't adjust the injectors - that can only be done (if at all) by a shop equipped with diagnostic equipment to determine the popping pressure, mist pattern, spray density, etc. Definitely not a job you can do by eye or ear or luck.
The same holds true of the injector pump itself - you can't service it. Only a shop with a Bacharach test bench setup can successfully work on an injection pump. Even then there's no guarantee - the pressures are very high and the tolerances are tiny and critical.
Did you remove the fuel shutoff from the tank and visually examine the screen? Did you check all the hoses visually to be sure they're not collapsing or shedding debris internally? Flushing alone won't clear crud out of fuel lines - it takes a pipe cleaner or cleaning brush run through them. Likewise for filter screens - they have to be brushed clean and blown clear. Ditto for all small passages anywhere in the system. It takes mechanical cleaning, not just a flush if you've got diesel bugs or other organic matter clogging the system.
I still think the system is suffering from an obstruction somewhere before the injector pump. Since it runs fine when you pump the priming pump, the injectors must be functioning at least somewhat satisfactorily and the injector pump is delivering enough pressure to pop the injectors and deliver fuel to the cylinders. Unless the lift pump is failing to supply fuel to the injection pump or the injection pump is incapable of drawing fuel in, the problem would seem to be a supply issue. That's my take on it, anyway.
Rich
The same holds true of the injector pump itself - you can't service it. Only a shop with a Bacharach test bench setup can successfully work on an injection pump. Even then there's no guarantee - the pressures are very high and the tolerances are tiny and critical.
Did you remove the fuel shutoff from the tank and visually examine the screen? Did you check all the hoses visually to be sure they're not collapsing or shedding debris internally? Flushing alone won't clear crud out of fuel lines - it takes a pipe cleaner or cleaning brush run through them. Likewise for filter screens - they have to be brushed clean and blown clear. Ditto for all small passages anywhere in the system. It takes mechanical cleaning, not just a flush if you've got diesel bugs or other organic matter clogging the system.
I still think the system is suffering from an obstruction somewhere before the injector pump. Since it runs fine when you pump the priming pump, the injectors must be functioning at least somewhat satisfactorily and the injector pump is delivering enough pressure to pop the injectors and deliver fuel to the cylinders. Unless the lift pump is failing to supply fuel to the injection pump or the injection pump is incapable of drawing fuel in, the problem would seem to be a supply issue. That's my take on it, anyway.
Rich
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greg_g
Super Member
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If it runs - even temporarily - there's no problem with the injectors. Or the injection pump for that matter. How long does it run for? Several minutes? If yes, then your hand primer is filling the fuel filter - which in turn is feeding the injection pump. Sounds however, like the lift pump is not refilling the filter. When the filter housing gets sucked dry, the engine quits.
Unfortunately, you can't simply replace the lift pump component of the fuel delivery assembly (what many folks refer to as the "injection pump"). because it's more convenient. And I'll explain that; the fuel delivery assembly consists of a low pressure side and a high pressure side. Lift pump, hand primer are on the LP side. They send fuel through the filter to the HP side. It consists of the actual injection pump component. But the components cannot be purchased/installed separately. You're stuck buying the whole dang $600 assembly.
//greg//
Unfortunately, you can't simply replace the lift pump component of the fuel delivery assembly (what many folks refer to as the "injection pump"). because it's more convenient. And I'll explain that; the fuel delivery assembly consists of a low pressure side and a high pressure side. Lift pump, hand primer are on the LP side. They send fuel through the filter to the HP side. It consists of the actual injection pump component. But the components cannot be purchased/installed separately. You're stuck buying the whole dang $600 assembly.
//greg//
i thoroughly flushed the tank, replaced the whole fuel bowl assembly and the screen in the tank, replaced the hose to the primer, and the screen in the banjo fitting as for all the other lines i have removed them and blown them out, i replaced the fuel filter and blew out all the return lines, when i crack the return line bolts loose on top of the injectors and prime it i get good fuel flow out of the bolts and when its running i cracked the supply lines loose to the injectors and i also get good fuel flow with the engine running which makes me want to believe that the injector pump is ok and maybe a couple of the injectors are bad. I dont believe anymore its a restriction problem because i have good fuel flow, i think it may be a lack of pressure? i am stumped and extremely frustrated!
Bob Rooks
Elite Member
Yes, you can purchase the lift pump separately. Bought one from Tommy recently. Something like $40.00 + shipping (which wasn't much).
BTW, the new lift pump comes with a new primer pump.
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Bob Rooks
Elite Member
What I found on mine was that the corrosiveness of the bugs had pitted the check valve seats in the lift pump so bad (and also the PRV on the fuel injection pump) That the lift pump would not work effectively above an idle, and the system would not hold pressure. Just running the engine over ~700 r/m would deplete the available fuel.
Video #1 shows the effect of a defective lift pump:
YouTube - Lift pump 1.mpg
Video #2 shows after the lift pump and PRV were replaced.
YouTube - New valve 1.mpg
I set the PRV a little high in the video, I have since lowered it to 35 psig.
Engine runs like a swiss watch now.
:licking::thumbsup:
greg_g
Super Member
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well i spent several hours pressure washing and rinsing with clean fuel and i did completely remove the screen in the tank and the screen in the banjo bolt.
i looked at ranch hand supply and it doesnt look like they carry parts for the 454 my engine is a 3105ABT are you sure the lift pump is part of the primer on mine i have found the primer assembly but it doesnt say anything about the lift pump.
i looked at ranch hand supply and it doesnt look like they carry parts for the 454 my engine is a 3105ABT are you sure the lift pump is part of the primer on mine i have found the primer assembly but it doesnt say anything about the lift pump.
Rich Waugh
Platinum Member
Bob said he got the lift pump from Tommy - that would be Affordable Tractor Sales, not Ranch Hand Supply. Both are great dealers. While you may not necessarily find some particular item shown online, if you give them a call they often have what you need.
Rich
Rich
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