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Discussion Starter #1 (Edited)
Truck is new to me, sat for an unknown amount of time with no transmission in it.

Its a 1995 2500 with the 6 lug semi floater/4l80e.
I sat the transmission under the truck plugged in and it will now turn over (neutral switch). But wont fire.

Lift pump works, and was ran with power to it from the battery after confirmed working for other diagnoses. I get 4 psi from the lift pump, the t fitting and fuel filter fitting both flow out diesel.

The shutoff solenoid did not appear to work, and was tested outside the truck and had no action. I removed the c-clip and plunger and installed it back in unplugged.

Ive tried it with both the optical sensor plugged in and unplugged, no difference.

When it has sat the glow plug light comes on for 10 or so seconds, after that it cycles 1-2 seconds. Also manually cycling the glow plugs works.
The truck whips over fast 200+rpm, has good batterys, and will just fire on one cylinder enough to kick the starter out.

Cracking the injector lines results in fuel but very little dribbles out. Not familiar with the electronic pumps and unsure if the solenoid by the injector lines would be the cause. Always thought when the pmd went out they would not send fuel to the injectors.

Edit: Tempurature is roughly 54F block heater was plugged in also. Diesel is relatively fresh.
 

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Welcome to Diesel Place!

Plug the fuel shutoff solenoid back in to the harness.

After the glow plugs have cycled, wait 30 seconds or so to get another full cycle. If you want a max glow cycle, unplug the Engine Coolant Temp sensor on the coolant crossover. Tricks the PCM into thinking it is -40*F. Also gives max advance on the IP to aid in starting. If/when the engine starts, plug the sensor back in.

Fuel dribbling out of cracked injector lines is normal. And that means the PMD is working.

If you haven't done so already, check for DTC codes. You can use a paper clip. Here is how: http://www.dieselplace.com/forum/63-gm-diesel-engines/21-6-5l-diesel-engine/16399-diagnostic-codes-obd-i.html
 

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Discussion Starter #3
Thanks, no lights come on ( i know some of the 95's needed the scanner) the temp sensor was already unplugged, looked like it had melted but I knew it would default to thinking its cold.

The crossover pipe is disconnected and i do get a puff of white smoke out of the driver side cylinders.
 

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I wonder if youre getting enough heat from the glows to fire the engine. You might just have to crank some air out of the system and fuel flow to the pump sounds questionable. Is that 4psi post filter while cranking or just with the LP running?
 

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Discussion Starter #5
I get 4psi at the IP from the filter.
I have quite a bit of cranking time in it and both bleeds show no air bubbles.


Could be possible some glow plugs aren't working. Last 6.5 I had, had bad plugs and would noticeably shake trying to fire.
 

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It sounds like you are close to starting. I would pull all glow plugs out and inspect them. I bet you have several dead plugs. Look at them as you pull them out. Are they wet or dry? If wet, when they are all out, spin the motor over and let it blow out the liquid.

Put in a full set of new plugs, or test all of the pulled ones. If any DONT instantly glow at the tip, they are bad.
If they are all good, test the glow harness ends for power.
 

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Did you put new batteries in there? or at least load tests the batteries one at a time.

The fuel can also be bad.

LP can jump override at the relay (HeavyChevy has a lot of pictures here on what pin to short) and let it running while you are cranking.
 

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Discussion Starter #8
Lp is already jumped, bother newer batterys (3 months old, pulled directly from another truck to this, load test alright)

Fuel sat for 2 weeks in cans and was put in yesterday. And came from the local station/bus depot.

Its seeming like weak fuel from the IP, but im not sure if thats possible, I figured it was either all or nothing.
 

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It takes a long time to crank, that is normal.
You may need to take out one of the GP and crank till you see fume.
Put the GP back and then crank it for the last time.
This should work assuming the engine is still good.
You also need a lot of diesel fuel, it cannot be only 5 gallon since the sender has not been working for a while it has to build pressure.

It has to build some pressure inside the engine.
It is like if you have been in a laying down position for long.
That is why 2 batteries have to be in top conditions.

There should be no air in fuel system also.
As usual crank with pause to cool down starter.
 

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Discussion Starter #10
There's at least 15 gallons, found a small pin hole in the fuel/water separator and bypassed that directly for the moment. Also have the intake off and it's still the same, puffs abit of white/grey smoke. Block heater has been on all night and the motors warm to the touch.

The neighbour also has a 6.5 dually and it whipped over and started without the glow plugs having enough time to cycle, so it's not cold per say.
 

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Discussion Starter #12
Talked them into letting me try it (Dont know them at all besides hearing it start every morning and down the road before it even fires on all cylinders)

But swapping pmds did nothing, mine works fine on theirs. Theirs has the same symptoms as mine. Their truck also cranked slower.
 

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I suspect your truck still have air in fuel.

May be bad fuel filter that already clogged up.
If you replace it, make sure you clean the bowl real good.
Spray some brake cleaner at the bottom and wipe them out till it is cleaned.
Then put a new filter in and bleed the air.

Did I say, it may take 5-10-20 mins of cranking if everything is good.
 
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Discussion Starter #14
Eliminated the filter all together, put a clear filter in place from the lift pump straight to the injection pump, no debris, no air bubbles just solid fuel to the injection pump.

Ive had over half an hour cranking time. Bleed the injector lines multiple times.
 

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Discussion Starter #16
Yep, all fuses are good, all relays are also good.

Have to swap out starters, the one that came with it is getting to the point where it goes to fire off whatever cylinder is getting that little bit of fuel and sounds like it grinds.
When I pulled it out it was a 6.2l starter. I have the newer gear reduction 6.5l to put in it
 

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Discussion Starter #18
Yep everything is intact surprisingly. The back window was full of gopher dunes stickers ( local fair/mud pit)

Looks like it last ran april 19th 2014 and was towed out of the mudpit (hence the transmission being shot)

But other then that the other couple videos from the year before looks like it wasnt beat on to bad besides being in the snow once.

The last owner was definitely not very competent,but at least kept it clean.

Weathers bad enough that Im done for today, Im still thinking something is up with the injection pump.
 
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