gman07

My dad ran our FL80 out of fuel, and we've been trying for about 2 hours now to get it started.

The filter's full and we're getting a solid stream of fuel at the banjo bolt on the IP (no air bubbles). After entering the pump, where exactly does the fuel go? I know how a VE works, but I've never looked much at P7100's.

Also, do the outlets where the high-pressure lines connect at the pump correspond to cylinder number? For example, does the front line on the pump go to cyl. 1? I'm thinking if we get fuel to the first 3 cylinders it should run from there. We can't crack the injector lines for lack of a decent wrench so we're taking the lines off the pump to get fuel there.

I'm assuming we'll just have to keep cranking until we get fuel out of the pump, then tighten the lines and crank some more....

And this had to happen at night when it's 10* ...

G1625S

If you've got fuel out of the overflow valve, the next step is to bleed the high pressure lines...sound like you've got a trip to the tool store ahead of you Gotta crack those lines at the injector to get the air out. You are right in that once you get 3 of them to fire, the engine will begin to run while you bleed the others. Good luck!

dslpower

Make sure the shut off solenoid is pulled up while trying to reprime. Also it would be best if you cracked the lines at the injectors, to purge the most air out of it.

gman07

Is it completely necessary to crack the high-pressure lines at the injectors? We cracked #1 at the pump until we got fuel to it, then tightened it and we're hitting on 1 cylinder. I'm thinking maybe we can just crack the lines at the pump instead of the injectors? I know it will take more cranking, but will it work?

Shut-off solenoid is up.

Thanks for the help guys.

G1625S

As long as air didn't fill the high pressure lines, that may work...but even a tiny bit of air can make it stumble and whatnot--I had air trapped for months untill I bled the lines at the injectors---smoothed my idle right out. On the Dodge, I give the starter 1 minute to rest for every 20 seconds of cranking...not sure on the bigger trucks, though

Forrest Nearing

crack the injector lines at the injector, this bleeds the air from the lines... once you've got fuel there, lock 'em up and you'll be good to go

Sidewinder

I find it helps to hold the "gas" peddle to the floor while cranking. My guess is it pumps more fuel to help purge the air faster. I don't know if it the correct way to do it but it makes it easier for me when I loose prime.

oldsmokey97

i have changed fuel filter and taken injector lines off MANY TIMES and have never ever ever had any problems with getting the air out of the lines.

I have never bleed anything. Just cranked for a little while and used the purge "push button" thing on the lift pump and waited for it to start sputtering and it would fire off.
After it fired off, Just hold the peddle to the floor and let it spit and spudder till it cleared out.

But, i guess the more fuel you are pushing from the pump, the less time it takes to clear the lines of air.

Lance

Forrest Nearing

good call, whenever I go to fire up after the fuel system has been opened, I give it a bunch of throttle... it definately pumps more fuel!

gman07

We cracked lines 2 and 3 at the injector this morning and got it to run. We plugged in the block heater and a battery charger last night so this morning it cranked over faster.

Thanks for the help

infidel

The reason bleeding the lines at the pump rather than the injectors doesn't always work is that air in the injector lines compresses rather than reaching high enough pressure to pop the injector open to purge the air. Air becomes trapped in an over and over compress/decompress cycle.

Forrest Nearing

I love those few moments where the engine transitions from stumbling to smoothing out

oldsmokey97

AMEN.

Sounds like heaven.

LOL