Fuel Bleeding Issue

[dtdoyle01]

Hope someone can help with this issue. I put an electric fuel pump on my 84 M1028. I can't get the system to bleed the air. I have fuel at the inlet to my fuel filter, and fuel exits heading to the IP. This entire fuel system has been rebuilt (IP, Injectors, fuel lines, dropped and cleaned take, sending unit) can't figure out why I can't get fuel through the IP. The manual pump that was installed got fuel to the injector. The electric pump I installed is a Airtex E8153. Any help would be greatly appreciated.

 

[Skinny]

I know it is new but maybe the outlet check valve on the IP is plugged?

 

[dtdoyle01]

OK, I just checked the fuel pressure using a Harbor Frieght combination pump and vacuum test gauge. Not sure if there is a special gauge that is used for diesel. The pump is rated for 10-14 psi. I'm getting 8 psi on this gauge. Again I do have flow out the exit on the fuel filter, but can't bleed the injectors.
Thoughts?????

 

[Skinny]

8 psi sounds like enough to get things going and running without issues.

If fuel is going into the IP with pressure, my next area to check would be if the IP solenoid is clicking on. Without it, no fuel is going to be delivered to the high pressure lines.

I'm going to back up a minute here. Why did you install an electric fuel pump? Was the fuel system run dry (ie. engine running fine, then ran out of fuel at some point)? Reason I ask it that if the engine was shut down and not cranked over with the IP connected, there would be no reason for air to get into the high pressure lines. Even if you rebuilt all of your low pressure lines, you would be able to bleed it out and the engine should fire right up. Let's get some more detail on what happened and why first.

Another tip if you do end up having to bleed the high pressure lines is to remove the GP's, disable the system, and crank the engine over. It will crank much faster and take the strain off the batteries. Plus it will bleed the injection system quicker if you go that route.

 

[dtdoyle01]

Here is the story in a nut shell. The truck has been down for almost a year now. The original problem, she would idle, but when I tried to to drive herI would hit the gas and I had no power, then she would stall, or if I would hit the brakes she would stall. I had a few other issues that plagued this truck, so the GL system and Vacumm system minus the vacuum pump were completely rebuilt.

Following advice that I read on the forum I started replacing the parts that others with similar problems were fixes. Up until I swaped the manual lift pump for the the electric, she fired right up, but still had the power issue. Swaped the pump, and I have the current problem.

It took so long to replace parts trying to fix the problem due to money. I have spent over $1000 on parts, and she's still dead in the water.

 

[dtdoyle01]

I just checked the solenoid. With the key in the on position, it clicks once when I first attach the pink wire. Then I don't hear anything. Is it suppose to keep clicking? And if so, does it click when the engine is running?

 

[dtdoyle01]

Answered my own question on the solenoid

 

[Skinny]

Regardless of whether you choose to run the OEM mechanical LP or an electric one, you still are having the issues so I would not focus there. Have you dropped the tank to look at the fuel sock? I would start there and work my way forward. I'm assuming you have changed fuel filters as well.

Once you have solved all of the delivery issues like replacing flex lines, clamps, filter issues, etc...you will be at replacing the IP.

 

[dtdoyle01]

My first post has a list of the things I replaced (IP, Injectors, fuel lines, dropped and cleaned tank, sending unit with sock, manual lift pump, electric pump.) I'm focused on this issue because before I added the electric pump and pulled off the manual one, I at least had the truck running. Now I can't get the system to even bleed. There is nothing else to change, and I still have the original issue plus this current one. I have zero miles on this truck since I have completed all this work.

 

[Skinny]

Who rebuilt the IP?

 

[richingalveston]

just trying to clarify the post.
You replaced everything(IP etc.), got the truck running.
Then the next thing you did was only change to electric fuel pump and now it will not run?

Rich

 

[dtdoyle01]

Badger Diesel out of WI did the IP and the Injectors

 

[dtdoyle01]

Yes that is the case. She did idle and accelerate when in park. As soon as I got her out of the drive way and hit the gas, I lost all power and it would stall.

 

[richingalveston]

That could be a bad IP rebuild.
If you could not get the truck up to power after the IP with the mechanical pump, the electric pump would not fix that.

If the assumption was everything else is new so it has to be the old mech. pump and instead of replacing it, you went electric, I understand the thought process.

A bad IP can run for a short time and then die. Both IP failures I experienced they would let the truck idle but would not work under load. I have however had a mechanical pump do the same thing.

IF you had the truck running with the mechanical pump, can you put it back on and see if it will start again? It will give you a chance to check the pressure with the mechanical vs. the electric. (a lot of work).

From what I have read, you can run the electric in front of the mechanical pump.

 

[dtdoyle01]

I guess I will contact badger and see if I can send him the pump back for testing. I did change the mechanical lift pump out. It was the second thing I did in the long history of these issues.

 

[epitts]

Just a WAG but check your wiring on your elec fuel pump. I had one wired per instructions and was sucking instead of pushing, reserved wires works fine now. YMWV