Fuel problem...injector pump is getting fuel but won't push fuel?!?!

[Thefarmboy21]

It seems like everytime I push the bicycle valve in the filter head I always get a bug puff of air and bubbles when the fuel runs out? Could air be getting in somewhere? I pulled the pin on the fuel/water separator too a few times and once got a bug spew of air there too. I've never messed with the fuel system on an idi, but it has a new fuel filter and a new return line/seal kit. Am I supposed to bleed the return lines in some way? The truck has not ran in several years....just been sitting awaiting a new motor.

 

[Agnem]

You should NEVER get air when you push the shrader valve. Your problem is upstream of the IP if this is the case.

 

[Thefarmboy21]

Hmmm....well I guess I'll start go from there then. Would it be a good idea then to just unhook my fuel line at the fuel pump and run it into a jug and see if it'll pump fuel from there? That way I'll either know it's between the pump and the tank or the pump and the IP?

 

[bghnkinf350]

Bypass that water separator for now. They are well known for letting in air. Next make sure you have more than a quarter tank of fresh fuel. Once you have those taken care of, we can start chasing down any other points where air is getting into the fuel system.

 

[Thefarmboy21]

Ok, so to bypass it I just take the lines out of the top and hook them together I assume? How many gallons does it take for a rear tank to be 1/4 full? It has about 4 gallons of fresh fuel now but I didn't notice the gauge. Shew....glad I'm finally getting somewhere...hope I don't have to change the stupid IP lol. That stupid fuel/water separator looks sketchy anyway....dad blew the truck up in 2002 :O

 

[Thefarmboy21]

So now I'm really stumped and aggrivated. I bypassed the fuel tank and water separator and just ran a fuel line from the lift pump down into a jug. Tried to prime it, nothin. Then spray some Ether in hit and it sounded like it hit and died. Took the return line out of the top of the pump and cranked it over....the return line was pouring fuel but nothing was coming out of the injection pump...is that right?!?!

Anyhow went I took the fitting off it had tons of pressure built up at the main return line with air and a bunch of fuel. I looked down in it and it had rust all in it even tho the FSS was working I decided to change the injector pump with the one of the blown motor that was nice an clean inside. Didnt wanna risk it so I changed all the metal lines too. Started cranking and cranking and cranking.....still no fuel to the
injectors. So we decided to see if it would fire off Ether again. Cranked and cranked and sprayed Ether didn't even try to hit?!?!?! Just whirled over AND it never did sent any fuel to the injectors. I had the lines OFF and I mean they are bone DRY! I just don't understand what it could be! It won't hit on Ether, has a different IP, the FSS and the cold advance are both clicking, the cold start solenoid throws the throttle back every time...I just don't see how it doesn't start?!?!

How do I test the glow plug controller/glow plugs to see if they are powering up? Even though that still doesn't explain the weird no fuel problem. I'm just so aggrivated with this thing! Someone help me lol!

 

[OLDBULL8]

Glow plugs and/or the controller have nothing to do with getting fuel. STOP useing ETHER or you won't have an engine to even mess with, bent rods, broken piston rings, cracked pistons ect.

Four gallons of fuel in the tank is NOT enough.
Hook up your hose from the lift pump into a jug of fuel.
Disconnect the line from the lift pump at the filter.
Got fuel there. OK. Rehook that line.
No fuel. Lift pump bad.
Disconnect the line from filter to the IP.
Got fuel there. OK
No fuel. Plugged filter or line.
Reconnect line to IP.
Remove the line (hose) on top of IP.
Got fuel.OK
No fuel. Screen plugged at inlet to IP. Check valve in outlet on top of IP stuck or defective.
Disconnect a couple of hard lines to the injectors at the IP.
Got fuel there. OK
No fuel. IP is shot. Possible sheared shaft.
Reconnect hard lines.
Takes a lot of cranking to fill the hard lines to injectors. Loosen all the hard lines at the injectors to bleed air. Retighten each when fuel is present.
Reconnect line from tank to lift pump.
Got fuel. OK
No fuel. Fuel too low in tank. Shower head in tank broke off. FSV (Fuel Selector Valve) defective. Air intrusion with the fuel.
Cranking engine should turn over about 300+ RPM. Stop cranking for 2 minutes after a 20 second crank to let the starter cool down. Keep a charger on the batteries when troubleshooting.
With the above procedure, you should be able to find your fuel problem.

QUOTE[Anyhow went I took the fitting off it had tons of pressure built up at the main return line with air and a bunch of fuel.]QUOTE
Re-reading your last post, if you had pressure on the outlet hose on top of the IP, there is something wrong in the return line to tank, if you were not cranking.

Spin the old IP by hand, there should be enough fuel in it to spit a little out if it's any good.

 

[RLDSL]

If after doing everything oldbull said, you still cant get it to cough, Ive run into many diesels that just dont want to bleed off by themselves for some reason or another, even when they have electric pusher pumps , and I found this nifty test rig works wonders for priming them up, especially if the ip has been bone dry.
Get a boat gas tank like used for outboards, and a long length of 3/8 fuel line with the boat hand primer bulb and an inline fuel filter and assemble that setup , fill the tank with diesel and attach the hose directly to the metal line going to the IP place teh tank on the roof so it will gravity feed once it gets going. crack the injector lines open and then have someone crank the engine withthe throttle flat on the floor while you squeeze that hand primer bulb like a maniac. you will be surprised how much pressure you can put to that thing, it turns out to be more than your fuel pump, that little hand bulb really shoves fuel through the IP, and when you have a stubborn air locked injection pump, it can be the only way to get it sometimes. When you start seeing fuel at injectors stop and tighten them down the crank and pump some more till you see more fuel etc. Dont crank too long at a time, dont want to fry your starter

 

[homelessduck]

How come on the visor of my truck ford recommends full throttle while cranking below 32 degrees, and half throttle above? I also saw the same thing by IH in a S series equipped with a 6.9.

I always thought the reason for this was to set the throttle at different positions for cold start warm ups. My cold start solenoid only holds the throttle at its current position , it won't push the throttle open .

 

[Thefarmboy21]

Yea I have the fuel tank unhooked and a line ran from the lift pump to a jug now. When I get back to the garage I'll unhook the return line to the tank and see if it's clogged.

BUT I did get shocked thru the key switch last night...now Ive started thinking that MAYBE the IP has power with the key on and it grounds out or something with the key switch in the start position?!?! I'll test that too and probably just run a jumper wire anyway because I haven't tried it up to this point. Well I did to test the FSS to see if it did anything different than the actual plug but I didn't leave it on there while I cranked it. This truck ran even after it was blown up but just had two holes in the oil pan....but I guess since it's sat for 10 years (2002) alot of little annoying problems can arise making it a pain to sort out.

 

[Thefarmboy21]

How do I check to make sure the FSS is actually opening? I ran a hotwire to the pump and still no fuel. The FSS is the one closest to the front right? I can here it clicking but don't see anything happen. When I apply power to the top one closest to the lines (cold advance?) the little needle jumps up and stays up even after I unhook it. My return line was clogged at the rear fitting where it goes to the big line at the fire wall but is unplugged now and still no fuel out of pump. (keep in mind this is IP #2) I'm just entirely frustrated. And to beat it all, k have a blown brake line and can't get my Clutch to pump up, so I can't even pull it to try and start it.

Also found a hot wire unhooked from the solenoid on the fender. It has two green wires into a single eyelet with about a 3/8 hole. Both wires bolt onto the solenoid and it was hooked up because you can see the wear marks. Maybe to the GP controller? Still nothing to do with the problem at hand I feel like.

 

[Thefarmboy21]

Is there anyway to test these pumps off the motor? I have two IP's with what seem like working solenoids both getting fuel but neither will put fuel into the lines/injectors. I can't just keep cranking on my truck. I'm thinking maybe a drill, a fuel jug and some jumpercables???

 

[Agnem]

Yes you can do exactly that. If you put 12 volts to the pump and spin it the correct direction, you can indeed make it function out of the engine compartment. However, I'd strongly urge you to discuss the actual problem in greater detail before resorting to such foolishness.

 

[Thefarmboy21]

Lol ok here goes as best as I can describe...

87 F-250: Dad threw a rod in the original motor, bought and installed a used motor that I have NOT heard run.

This is my setup: fuel jug on the garage floor, hose to NEW lift pump, then original plumbing the rest of the way. Has a new fuel filter full of fuel, has fuel everywhere I listen a fitting. Line going into the IP has fuel, return line out of the IP has fuel, ran a direct "hot-wire" to the FSS. FSS clicks everytime you apply voltage as well as cold advance and cold start solenoid. Cold start advance needle pops up everytime you apply voltage...

Problem: with fuel and voltage the IP will NOT push fuel out of the injector line ports! The IP on the used motor would not push fuel tho it had fuel and voltage and seemingly working solenoids and now IP #2 (off blown original motor) has exactly the same problem, fuel, voltage, seemingly working solenoids, but no fuel out the injector line ports on the back of pump when you crank the engine.

I am under the impression that all the pump needs is fuel and voltage to the FSS to work. The FSS is the one closest to the timing gear correct?!?! Both pumps had exactly these things and no fuel. I just find it hard to believe that I have two bad pumps especially since the blown engine ran even after it threw a rod.

I'm out of ideas!!! Thanks to everyone for their imput thus far

 

[Agnem]

It sounds to me like your issue is that you have no injection lines or injectors on the lines. The pump cannot prime properly without some "back presure" as it were. Put the rest of the fuel system together, and crank the engine with the pump at full throttle. After 10 seconds of cranking, go around to each injector and momentarily loosen the injector line nut at the injector. You should hear a little pffssstt... of air. This tells you fuel is coming down the pipe. You will need to do this mutliple times. Be sure to keep the glow plugs disabled (disconnect the power contactor input cable) and do not overheat the starter.