1989 Ford 7.3L Diesel Engine - proper way to bleed fuel lines
I have a 1989 Ford E350 with the 7.3L Diesel engine. I am a Diesel newbie, so here is what I did.
I replaced the Fuel Filter in the Fuel/Water separator. Unfortunately when I went to start it up after the filter replacement, I left the water separator drain "full open" instead of "closed".
I then started the engine, it ran for a few seconds and then died. When I stepped out of the truck to take a look there was diesel fuel pouring out of the drain tube.
I then quickly closed the drain and tried to restart the van. It would not start after repeated attempts. By this time the batteries were low and I am recharging them now.
I am thinking I now have air in the lines, so I need to bleed the fuel system. Based on what I have read on the forum, It looks like I need to:
1. Purge air from the filter by cranking the engine while pressing the "Schrader valve" on the top of the Fuel/Water Separator until a strong stream of diesel squirts out.
2. If the above does not work, Loosen one or two of the metal injector fuel lines by 1/2 turn and crank the engine until strong stream of diesel squirts out with no bubbles in it. Then tighten them back up and try to start it.
I do have a few questions on the above:
1. Does the above assessment sound right?
2. Does the filter purge usually get it going?
3. If I do have to loosen the fuel line(s)(Kind of worries me due to the lines being rusty[at least on the surface]), how many do I loosen and does it matter which ones?
4. Do I have to wash the fuel off the engine after the above, before I try to start it or after a 5-10 minute run?
5. Do I have to "floor" the accelerator pedal when doing the above?
As luck would have it, we had planned on going camping this weekend (if I can get it started)
Sorry for all the questions and thank you all in advance for your advice.
Step #1 is correct. Step #2, you'll see very little fuel from the injector lines at idle, but opening them provides a low pressure path for air to purge, instead of being forced into the injectors. I usually crack two lines, one on each bank, if it doesn't start while purging the fuel filter per step #1. Once it starts, I tighten the lines with the engine running. It should start at idle, there's no need to open the throttle.
A word of caution... These diesels require a lot of torque to crank, and it's easy to burn up a starter. Crank for 15 seconds max per cycle, and allow a couple of minutes between cycles for the windings to cool off. If you have to crank it more than a half-dozen times, or if you smell electrical smoke, stop, put the batteries back on charge, and do something else for an hour or two.
If your truck had difficulty starting cold before you got air in the lines, it will be even more difficult now. Also, leaving the key in the ON position for extended periods with the engine stopped can burn out the glow plugs. If you suspect the GPs aren't all up to snuff, using the block heater can help, even in warm weather. And it can't hurt at all.
Don't feel too dumb about the water drain being open. I did the exact same thing last week when I swapped my filter. Except I have an electric pump and dumped about 2-3 gallons on the ground before I realized it was leaking. DOH!
For my 89' F250, Chiltons says when replacing the fuel filter "do not add fuel to the new fuel filter. Allow the engine to draw fuel through the filter." Seems weird, Where does the air go? I have done this though and had success. Today i went in to buy a filter and the gasket for the water trap was wrong, so I opted to get a filter with a built in water trap. Looking at it i am worried that the old separate water trap has a self bleeding device next to the water drain. Is this true? And if so will i have to bleed the injectors now?
Thanks man, I put as much clean diesel in the filter that i had and cranked it till it fired up. Ran a little ruff at first but it is running smooth again. Think it is good, might try bleeding at injectors later.
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