I have an 84 E350. The engine is a 7.3 IDI from an 89 E350 donor van. I mated it to an E40D.

I have no history on the engine before I got it. In the three and a half years since I installed it, I have driven it 65K miles. It has treated me well, always started easily hot or cold, except when it leaves me stranded, which it has now done four times.

The first time that I was stranded, I allowed a tank I was running on to run dry. I got it hauled home and the next day it started without too much trouble.

The next two times involved air from empty tanks although it had access to fuel in other tanks. The plumbing for the three fuel tanks is a work in progress. The second time I ran down the batteries trying to start it, got towed from the city crosswalk to an adjacent hotel parking lot, got a room, hauled all four batteries and my little charger up to the room, and charged them overnight. The next morning, I reinstalled them, bled the filter for the Schraeder valve, and it started with only slight hesitation.

The third time, it was a Wal-Mart parking lot, where I ran the batteries down trying to restart it, camped for the night, got several employees the next morning to push me to the service area, and borrowed their larger battery charger. By this time I had replaced the Schraeder valve with an electric valve and a catch-can. I bled the filter and the engine started with only a little hesitation.

The common element above seems to be the overnight wait.

Today I was in the middle of Illinois on the way from Florida to home in California. We had been in Florida to attend a National Speleological Society convention which just happened to coincide with their annual Hurricane Festival. I pulled in to a highway rest area and while checking things found a fuel leak at one of the injector fuel return fittings. I had some parts with me so I did what I hoped would fix the leak. This involved disconnecting two injector lines from their injectors, replacing one return fitting, and swapping some o-rings around. After I had reconnected everything it started instantly, did not leak, and immediately quit. This is a symptom I have seen before, where it will start on the fuel that is apparently in the engine, fail to get any additional fuel, and stop.

For the next five hours I occasionally tried to start it, with no response. At that point a guy came along who was a motorcycle mechanic returning from a model airplane meet. He had nitro because of the airplanes and a can of Wal-Mart house brand brake parts cleaner, just because. He suggested we try the brake cleaner first. After the first squirt, it seemed like maybe it wanted to start. I doubled that and it seemed a bit more willing. I doubled that again and it sounded like it was trying to hydrolock, but it started. It took only about a second to smooth out, and has worked fine the rest of the day, including several restarts and about a hundred more miles of travel.

At this point would anyone like to explain:

Why does opening the injector and return lines apparently cause the system to fail upstream? The supply pump is electric so I am able to get fuel to the engine prior to trying to start it.

Why I can grind on the thing on and off for several hours and apparently not get the injection pump to function but one kick with some brake cleaner will bring everything back to normal?

When I got it back on the road, I went to the next Wal-Mart a few miles up the road and bought two cans of brake parts cleaner and two cans of starter fluid. In order to get the brake parts cleaner into the engine, I lifted the cover on the air cleaner as far as I could, which was about one inch, guided the spray tube on the brake cleaner can to the center of the air cleaner and then bent it down so that it aimed at the outlet of the air cleaner. Of course I couldn't see what I was doing, I had to do it all by feel. I found it interesting that at Wal-Mart, the brake cleaner has a tube, but both the house brand and name brand starting fluids do not. Without that tube I would have had to remove the air cleaner, which is a project all by itself.

Unless someone can suggest a sure way to avoid this situation in the future, I am seriously considering plumbing an ether cannister, with a cockpit control, into the intake manifold.

Ray

 

i feel your pain
i still have air intrusion problems after installing a brand new return line kit

 

You have all the symptoms of fuel drainning back to the tank due to an air leak. You should make sure all the injector return lines and O rings are good. You should have a look at the water seperator in the fuel line, if fitted, these are well known for causing this problem.

 

i will look in to that

 

You could also install a valve that only allows fuel to go to the engine but not back out. Sorry cant think of the name of it...

I wouldn't use ether or starting fluid on the truck as its really bad on them.

 

Intruding FROM where, TO where?. The fuel return system is open to the atmosphere in the tank. I have never understood how having air in the return system up-stream from the return at the tank could cause the injection pump to fail to supply fuel.

I replaced injector return fittings, tubing, clamps and O-rings. What I got for my efforts was O-ring leaks where I never had them before. I got them fixed and here I am in the middle of the country with leaks again, and this is not the place to deal with it.

 

Did you note my statement that the supply pump is electric? I know that I have air-free fuel at the top of the filter.

Since I got it running yesterday I have driven 670 miles, leaky O-rings and all.

 

It is called a one-way check valve. The electric fuel pump has such a valve.

The "leak" - which I created by disconnecting and reconnecting the lines and tubing - was not in the line going to the injection pump, but in the return line going to the tank. And that line is open to the atmosphere anyway. So why should the injection pump care?

I wouldn't use starting fluid either. But as the guy who loaned me the cleaner said "what are you going to do?" And after one kick, all is well.

 

from what i understand about it.... the air comes in and goes to the higest point which is your fuel filter and alowes the fuel to drain through the return lines back to the fuel tank wich emptes the fuel filter
now you get in try to start it
glow plugs come on draining the battery
then you crank it over draining the battery
filling up the filter draining the battery
glow plugs cycling draining the battery
filter finaly full it fires if ther is enough battery left to turn the starter fast enough

i have been checking all the conections........from the tank to the pump to the water seperator to the filter to the ip to the return lines to the selector swich to the tank .
so far i think i have the engion done....
broke the return line on the fuel tank selector valve (maby a blesing in discuise replacing that might fix the fuel gage that was not working) and found a spot where the metal fuel line got crushed when i did my engion swap

 

I have minimized some of those by having four batteries, an electric supply pump, and an electric filter bleed valve. I think I will move the bleed valve to the input to the injection pump.

 

let us know if that works
i have a clear return line coming off the filter housing
im thinking i might make them all clear
glad my deisel is not my daily driver

 

When the engine is not running, any air leaking into the return system will let the fuel drain back to the tank.

Works just like a straw down in a drink glass.
Put your finger over the end, raise the straw up and liquid will stay in the straw.
Remove your finger and let air in, the liquid returns to the glass.

The engine is higher than the fuel level in the tank.
So any air leaking into the return system breaks the vacuum and lets the fuel drain back to the tank.

Air infiltration is the hardest thing to find and makes diesel owners crazy.
If you see fuel leaking out, air is leaking in.
Air will leak into places that fuel will not leak out of, an air molecule is much smaller than a fuel molecule.

In theory, if you let the electric pump run for say two minutes before you try to start, the air should be pumped back to the tank.
If it is not, that makes me think you have air leaking into a connection or line before the electric pump.

When replacing O rings, replace them and the return lines, all of them at the same time.
If you don't you will be chasing air leaks forever.
It don't take to many miles of hot fuel returning through the return lines to make the O rings hard enough that they will not seal if disturbed.
So once you change all the return lines and O rings, do not disturb them.
If the tees are deformed or real old, replace them when you do the O rings and lines.

You stated you had three tanks which was a work in progress.
Any chance you are sucking air in at one of those connections?

Inspect the fuel supply lines, the clips that hold them to the frame are great places for air intrusion if the lines are rusty by the clips.

 

Your fuel system sounds about like my complicated mess. 2 rear tanks with a swtich on the dash then a tank in the bed with a 2 way mechanical switch next to my seat through the floor which will use either the bed tank or factory tanks. If I select the bed tank then the return line will fill up which ever tank is selected on the dash. Pluse an electric fuel pump is in line right before the lift pump and is under my seat next to the mechical switch.

If you have fuel bleeding down and its not leaking anywhere, I would check your lift pump. I Know you have an electric one i have one as well but alot of electric fuel pumps like mine will allow fuel to drain slowly back down where as the factory lift pump should not. If the factory lift pump is defective, any air intrusion will alow the fuel to fall and the defective pump will not stop it. I would replace your lift pump first since its very easy and cheap starting point compard to other options. I would also check all your fuel connection again under the van along with the valves and make sure they are all in good condition. Yes, you may have air intrusion somewhere else but even with that, a good lift pump will not allow the fuel to drain. not garenteed but its what I would start with. Just my 2 cents.

Also, If the engine is hot, do not use either or equivelent. The hot for some reason will start to hydrolock only draingin your batteries and wearing out your starter quicker. I can get mine running on 1 battery in any conditions wether its cold and/or I run it out of fuel.
I guess each truck is different but I let it sit with the electric pump on for a coupple minuits while occasionally pressing the shreader valve to drain some air on the fuel filter. Then I crank for no more than 20 seconds (sometimes less) then sit for a coupple more minutes. I have yet to be stranded but for somereason I forget how much fuel I actually have in my tank. Thank goodness for the twin tank setups. Well, good luck

And lastly, My fuel setup is actually fairly good and is fairly simple since I understand it. If you want or need any info on how mine is setup with the 3 tanks, let me know and I can send you a diagram or explain in detail of how mine is setup.

 

Dave, you may have missed a couple points. The "leak" was one I created when I disconnected some things to try to fix an O-ring leak. Apparently that caused the injection pump to loose it's prime. Bleeding the supply system up to the filter did not help. Apparently the shot of cleaner caused the engine to start, and that spun the pump fast enough that it picked up fuel. That was two days and over a thousand miles ago, and all is well. I am going to start another thread on pumps.

You may recall the "third O-ring", between the line fitting and the return T, to keep the T pressed down. It was not well contained and blew out. At Ace Hardware I found a neoprene washer, 3/8 ID about an inch OD. Works much better.

 

is it possible to pressurize the fuel system with air maybe 3 psi and use soapy water to find the air leaks ???????????????????