Connecting the famous pink wire

[Chenobles]

Greetings!
My very first post about my very first CUCV. I am a complete novice, so please show some grace.

I have the infamous crank-no-start problem on my 1986 M1028A1 (has a welder, generator and compressor). Purchased it from a government auction and was told it ran when parked.
I have done most of the things recommended in the TM and on this site…new batteries, new fuel filter, new GP relay, tested all glow plugs and GP module, but no luck starting it. Not even a sputter. I unscrewed a couple of fuel injectors and noticed wetness (I assume there is fuel going to injectors).

Now to my main question. I have noticed that the pink and green wire connections to the injection pump are routed differently and look different than anything I have seen on here (see attached photos). I am wondering if this is causing or contributing to the problem I am having. Could someone tell me if these wires are properly connected?

I am also considering draining out all the fuel that came with the vehicle and putting fresh diesel. The vehicle has a large fuel tank that was pretty full when I got it. I would prefer not to have to deal with draining and handling that much diesel, if I can avoid it. Does anyone know of test strips or test kits I can use to determine if the diesel is still good?

Thank you, and forgive my long winded post.

 

[WWRD99]

Have you bled the fuel filter? Pumped it till fuel comes out? Once that's ok...yes loosen injector lines...if you're worried about not getting fuel out put a clear return line on the ip...you'll see it quick if not. Those wired connections on the ip are fine...not stock but should work ok. It will take a bunch of cranking to get fuel out of the lines. Don't crank to long without giving the starter time to cool down. Make sure you have the front starter bracket on too...look it up if you're not sure.

Sent from my SM-S906U using Tapatalk

 

[Mrgior31513]

One thing I've learned about diesels is you want to make sure the fuel is primed as well as you can get it. Full sized pickups, large industrial, small generators: it's something I've learned to check first.

 

[Barrman]

The pink wire in a stock configuration is hot with 12 volts when the key is on.

The green wire when stock goes to the sensor at the outside rear of the passenger head. That sensor has another wire that is hot anytime the key is on.

The sensor is supposed to put power to the green wires anytime the coolant is below 94° F. The green wires are supposed to plug onto the cold timing advance solenoid and the cold fast idle solenoid. Yours are basically bolted on. Then they are spliced into the pink wire which is also incorrectly bolted on.

However, your set up should work if power really is getting to all three points. When running, it won’t be correct though. But it should run.

The injector lines will seep fuel when opened. That doesn’t mean new fuel is getting there under pressure.

 

[Chenobles]

Have you bled the fuel filter? Pumped it till fuel comes out? Once that's ok...yes loosen injector lines...if you're worried about not getting fuel out put a clear return line on the ip...you'll see it quick if not. Those wired connections on the ip are fine...not stock but should work ok. It will take a bunch of cranking to get fuel out of the lines. Don't crank to long without giving the starter time to cool down. Make sure you have the front starter bracket on too...look it up if you're not sure.

Sent from my SM-S906U using Tapatalk

Thanks for the pointers. Yes, I bled the filter until fuel came out. I will put a clear line on the IP return, loosed the injector lines and crank away. How much cranking are we talking? Upwards of 30 times? I will be sure to make sure the starter bracket is in place.

 

[Barrman]

Crank for 20-30 seconds, let it sit for 2-3 minutes, repeat. Here is a video about running an IP dry and priming it again:

 

[Chenobles]

The pink wire in a stock configuration is hot with 12 volts when the key is on.

The green wire when stock goes to the sensor at the outside rear of the passenger head. That sensor has another wire that is hot anytime the key is on.

The sensor is supposed to put power to the green wires anytime the coolant is below 94° F. The green wires are supposed to plug onto the cold timing advance solenoid and the cold fast idle solenoid. Yours are basically bolted on. Then they are spliced into the pink wire which is also incorrectly bolted on.

However, your set up should work if power really is getting to all three points. When running, it won’t be correct though. But it should run.

The injector lines will seep fuel when opened. That doesn’t mean new fuel is getting there under pressure.

Thanks for the feedback. I did a little more digging and here is what I found.

I peeled back the black tape around the pink wire and found a green wire that has been cut. I’m assuming it is the green wire that goes from the sensor at the outside rear of the passenger head and is supposed to plug onto the cold timing advance solenoid and the cold fast idle solenoid. Before I restore the wiring to its original configuration, can you think of a reason/benefit why someone would splice the green wires into the pink wires like I have in my current set up? Wouldn’t that cause both the cold timing advance solenoid and the cold fast idle solenoid on the IP to always have power when the key is on, even if coolant rises above 94° F? That can’t be good, right?

It also seems to me like in order to prime the IP, my version of disconnecting the pink wire would be to unbolt the green wire that is bolted to the IP cover, so that the IP on/off solenoid is de-energized during priming.

Finally, upon closer inspection of the name plate, the IP seems to be intended for the 6.5 L diesel engine military vehicle from 1995 - 1997. The pump model, part number and application are:

Model: DB2831-5209

Part #: 12555697

Year: 1995-97

Engine Application: (Military) - N/A, 1.2 cSt

Thoughts on using an IP intended for a 6.5L engine on a 6.2L engine from 1986?

Thanks for all the help!

 

[Barrman]

That is a 6.5 IP. Maybe your engine is a 6.5? Here is a video about what the numbers on the pump mean:

It also shows the pink wire and green wire stock attachments.

Depending on where you are in New Mexico or where the truck was. Advanced timing and higher idle might have been needed just to make it run at high elevation. The proper way of dealing with that is to set the timing of the IP further advanced.