bleeding fuel injection lines

[galeo7171]

I am trying to bleed the air out of the fuel lines at the injectors. I have read on here to crack the lines and start until fuel comes out. Am I supposed to completely remove the lines from the injectors or just loosen them a little? I have replaced all fuel components including, IP, fuel pump, injectors, spin on fuel filter etc . How long should it take to bleed out the lines after replacing all this? It seems like I've been cranking forever, I even killed one of the cheap Chinese starters.

 

[Keith_J]

It should not take that long to purge the system. Loosen all 8 lines at the injectors, just a turn or two is all it takes. Also, flooring the accelerator will greatly speed the process. It will not start with the injector lines loose.

Before you kill another starter, make sure the priming system is working, you must have fuel out of the vent with the engine cranking (mechanical priming pump) or ignition on (electrical fuel pump). Also, you can greatly speed the priming process by removing all the glow plugs. Naturally, it won't start. But only do this with the injector lines loose, otherwise you could have a fire hazard with atomized diesel spraying everywhere.

 

[galeo7171]

Hmm. I've been cranking over the truck with all the injector lines completely off the injectors in an attempt to bleed the lines. I've installed an electric pump and blocked off the mechanical pump. I'm getting plenty of fuel to the filter, just not to the injectors. I'm going to tighten the lines back on the injectors then just loosen them up, maybe having them all the way off is my problem..

 

[Keith_J]

Is the pink wire connected to the fuel shut off solenoid? Does it have voltage when cranking? Measure the current through this circuit, should be at least 5 amperes.

 

[galeo7171]

I haven't tested the amps on the pink wire, but when I turn the key in the on position and remove the pink wire I can hear a clicking noise .

 

[doghead]

Maybe you should start a new thread for each of the 8 fuel injector lines too.

I've told you before, continue your threads, to get the best results. Nobody wants to look for your other threads to get all the information for your situation.

If you do this again, you will loose your privilege to post.

 

[galeo7171]

Maybe you should start a new thread for each of the 8 fuel injector lines too.

I've told you before, continue your threads, to get the best results. Nobody wants to look for your other threads to get all the information for your situation.

If you do this again, you will loose your privilege to post.

So, after typing all that out, you still couldn't take a little time and maybe throw some suggestions my way on what to do to fix my problems?

 

[swbradley1]

I don't have a CUCV but I can't believe that there isn't some information in the TM. Keith has already given suggestions.

You are gaining a lot of experience by fighting the problem. My first lesson would be cracking the lines doesn't mean taking them off. Second, just because a solenoid clicks doesn't mean it is working correctly

Any diesel I have worked on if the fuel system is working and you crack the lines fuel comes out when the engine is cranked (mechanical engines). IF you don't have fuel at the injectors when cranking then it is back further, maybe the IP or solenoid or pump.

Start at the pump then work your way to the lines. Somewhere along the way something isn't working or blocked. It is called step-by-step troubleshooting.

 

[Ken_86gt]

Since I have not read any of your other threads, I would start at the beginning. It seems that you changed out the entire fuel system. Have you properly primed your fuel filter- and you see the fuel coming out of the vent when you loosen it?

When primiming the system you don't have to remove lines, usually cracking them open is sufficient. It does not hurt to remove them, probably a waste of effort though.

 

[Warthog]

Sounds to me like the fuel shutoff on the IP is bad. Just because it makes a noise doesn't mean it is good. Maybe it is the wrong voltage.

 

[doghead]

So, after typing all that out, you still couldn't take a little time and maybe throw some suggestions my way on what to do to fix my problems?

Nope, And I didn't waste my time merging your threads either. (as I have in the past).

 

[Warthog]

If anyone is wondering about DH's stance in this thread, this is the 6th thread about IP issues for the OP.

It helps everyone follow along if all the questions are together in one thread. It helps everyone get a clear picture of what has happened, what has been tried, and what didn't work.

It also helps everyone by not wasting their time rehashing the same items.

 

[wayne pick]

If you guys recall, a few months back, a member had the same problem with the IP solinoid. After pages of posts and replys, it ended up being a bad engine ground. Sometimes we over think the simple solution. Not to brown nose, but im with DH. Trying to diagnose an issue thats scattered over three threads gets confusing, and getting into a verbal judo match with a moderator is a lose lose situation. Here's my take on the problem. The OP either plumbed or wired the electric fuel pump wrong, or did not fill the spin on filter all the way to the top, or not at all, or plumbed it wrong. There is usually no provision to bleed the spin on head unless you do it yourself. It's a fuel delivery problem.

 

[galeo7171]

If you guys recall, a few months back, a member had the same problem with the IP solinoid. After pages of posts and replys, it ended up being a bad engine ground. Sometimes we over think the simple solution. Not to brown nose, but im with DH. Trying to diagnose an issue thats scattered over three threads gets confusing, and getting into a verbal judo match with a moderator is a lose lose situation. Here's my take on the problem. The OP either plumbed or wired the electric fuel pump wrong, or did not fill the spin on filter all the way to the top, or not at all, or plumbed it wrong. There is usually no provision to bleed the spin on head unless you do it yourself. It's a fuel delivery problem.

A bad engine ground would explain why my starter is acting real slow, right? Also, with two fully charged batteries (still need to load test them, they are new Interstate batteries though), my volt gauge on the dash stays in the yellow when I turn the key to the on position. When the glow plug relay clicks, the volt gauge drops into the red. Another sign of a possible bad ground? The electric fuel pump is working as it should, I'm getting plenty of fuel to the filter. I did fill up the fuel filter before installing.

 

[galeo7171]

Sounds to me like the fuel shutoff on the IP is bad. Just because it makes a noise doesn't mean it is good. Maybe it is the wrong voltage.

I'll check the voltage in the morning and see what it reads

 

[wayne pick]

Fully disconnect all the battery cables and clean them including the ground buss on the firewall and the engine ground wire or strap. You never know, bad grounds can cause problems.

 

[galeo7171]

Fully disconnect all the battery cables and clean them including the ground buss on the firewall and the engine ground wire or strap. You never know, bad grounds can cause problems.

Will do. I know I removed the engine ground that comes from the gound buss to the intake manifold and ground strap when I took the manifold off to replace the IP. Maybe I didnt hook those two grounds back up properly? If I remember correctly, both of the ground wires were bolted to the intake manifold by one of the manifold bolts. I also remember there being two nuts on that one bolt.

 

[antennaclimber]

Are you sure that you are getting fuel to the IP?

You have stated that you are getting fuel to to the filter, but is it getting to the IP?

I would disconnect the glow plugs until you find out why the fuel is not getting to the injectors.
This will save some wear on the glow plugs and reduce the drain on your batteries during the trouble shooting process.
Once you are sure that you have fuel to the injectors, then reconnect the glow plugs and try the normal starting sequence.

Karl

 

[galeo7171]

Are you sure that you are getting fuel to the IP?

You have stated that you are getting fuel to to the filter, but is it getting to the IP?

I would disconnect the glow plugs until you find out why the fuel is not getting to the injectors.
This will save some wear on the glow plugs and reduce the drain on your batteries during the trouble shooting process.
Once you are sure that you have fuel to the injectors, then reconnect the glow plugs and try the normal starting sequence.

Karl

I have fuel weeping out of the disconnected fuel lines when I turn the motor over, so I'm guessing that fuel is getting to the IP. I will take out the glow plugs and continue to troubleshoot, thanks for the suggestions

 

[wayne pick]

Also, make sure the pink wire, not the green wire is indeed going to the IP solinoid terminal. If you connected the pink to the cold start solinoid, that is what you hear clicking. If you have a bad temp switch and have crossed the wires, the IP solinoid will not energize. Im not sure if the spade terminals are the same size. I never looked at them that closely as I always connected them as they should be.