• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

HELP!

Messages
27
Reaction score
45
Ok so this is going to be kind of a long post so PLEASE stay with me. lol. We bought a 1993 C3500 6.5 turbo diesel knowing it doesnt run. The kid we bought it from had no idea what was wrong with it he just jumped into it blind. So did we.. BBUUTTT for $1400 we could not pass it up. I have talk to the owner the kid bought it from and he said he wasnt sure what was wrong with it but he thought the injection pump was out or going out so he replaced the lift pump in hopes it was that but he "is to old the keep messing with it". The kid had put new batteries thinking a quick battery swap would magically solve all problems and the truck would run. He was wrong got frustrated and sold it to us. We were thinking okay great. Lines need to be bled because well the lift pump was changed and it stopped running. Driverside lines bled, front passenger side line bled... Heres where my questions come in....
Is there any special way to bleed the other 3 lines on passenger side with the dang turbo in the way?
The glow plugs are about 3k new and do not look bad, just mildly used. Is there any sense in replacing them?
It is getting spark. It is definitely getting diesel to the driver side and first line on passanger and...
Any new suggestions? I dont want to go into it blindly and start throwing parts at it.
 
It is getting spark.

Well... There is yer problem right there!!! Take apart WTF ever is sparking, clean it, and tighten it back up so it doesn't spark anymore. You may have to replace battery cables, if they be the spark source, and should switch to the better top post connections. The double positive connection on the passenger battery, a classic GM Hack Job, likes to crush and become loose.

No Sparky it might starty!
 
Welcome.
DO NOT USE STARTING FLUID!
If you already did or suspect the kid did- expect damaged glowplugs. But address that later, a couple things first.

So you are right to not throw parts at it.
However, one part to add right now is: replace the fuel return line on the ip (injection pump) with a piece of clear tubing.
Any hardware store sells it. 1/4” diameter about 5” long. Buy 2 screw style hose clamps to fit the new hose while you are there.
About $5 and less than 5 minutes to swap.
this is so when cranking or running, you can see if there is bubbles traveling through (or other contaminants). Diesels (especially this one) can suck in air and it reeks havoc on the system- will definitely keep an engine from running or if it runs can run poorly.

This is the first test to verify from GM after you have proper ranking speed- which btw, what is yours?

loosening the last 3 injector nuts is a pain. If you loosen the easy sideand a little jiggle to know the line is free- try cranking it. Do you get fuel coming out? It won’t be a lot. I describe it as a ‘spit’ from a 6 year old kid each revolution.

If you don’t get any fuel from the injector lines, Are you seeing fuel flow through the clear line?

If you are getting fuel from the injector lines- bleed the ones you can get to. Check for air (bubbles) in clear line.

Areyou getting any smoke out tail pipe when cranking? If so what color and does it smell like diesel fuel or antifreeze?
 
Will be buying clear hose tomorrow.
We loosed injector lines one driver side and then front one and very back one on passenger side. (One at a time) and cranked until it started spitting and tightened back down.
No smoke except on the RARE occasional crank and it is white then goes back to no smoke. It smells like fuel.
And about the starter fluid. The kid did said he used it. So I will add glow plugs to my list.
He also decided to take apart most of the dash to try and put an aftermarket stereo in it and left it in pieces when he sold it to us. I will post a picture of that in the morning
 
Ok- awesome you are getting fuel out injector lines- over half the battle is won.

go to local parts store that is AUTHORIZED AC Delco seller. There are a ton of knock offs out there.
Get: AC Delco 60G only!

When removing them if they unscrew but dont slideout- stop. They are swollen and there is 2 ways to do it. The hard way or the harder way. Leroydiesel.com sells a tool that is worth buying. Still a pain to deal with, the other way is removing it and the tip WILL break off 90% of the time. You have to remove the injector and use a 90° needle nose plier to remove them. There is a chance it can fall down ontop of the piston and that is a nightmare. So if you think they are swollen and can’t wait for the tool- remove the injector first and get ahold of it before it breaks. I can show you pics of my destroyed piston when that happens- DO NOT believe the lie online to just break it and leave it. Many ruined engines over that.

Btw, these delco plugs dont swell, so that is why they are crucial. Add a bit of anti seize tothe threads of the new ones going in.
DONT ever use a battery booster for cranking without disabling glow plugs. The higher voltage ruins them.

What is your RPM while cranking? This is a crucial thing.
 
Will be leaving dash until running and driving. It was just where the ac/Heater switches were and vents and radio were.
Will have to look at rpms when messing with it tomorrow to be 100% But I want to say 3-4k. Sometimes 5k.
We only own Chevrolet so ac Delco is only thing we put in our stuff.
And so far all 6 of the lines we bled none of them stuck they all slid out like new injectors but as far as we know they haven't been replaced.... ever
 
Hopefully a slip and meant 3-4 hundred not thousand. ?
And meaning to say you slid out the glow plugs easily. ?

let us know results
 
Night and day difference between gas and diesel. So when you go on about a spark I got to wonder if you are yanking our chain: The description you type on here is our only clue as to what is going on with the truck, period.

I suggest you post a video of it cranking as we can generally tell by ear if it's fast enough. No, just spinning over ain't good enough like spark ignited gas engines that can barley turn and start. (Thus the legit concern over battery cables maybe sparking.) The video needs to be focused on the dash to show us key on bulb check, SES light, Glow Plug lights cycling etc. Door open so we can hear it crank after the glow plug light goes out. 30 seconds max cranking before a 2 min cool down or you will find out how much fun starters are to replace.
 
You need to do diagnostic of the fuel system and the electrical system.

Make sure you have enough fuel, 1 or 2 gallon is not going to start the truck.
Old fuel will NOT start the truck.

Load (not Voltage) test the batteries one at a time. I am assuming it has 2 (two).
Also make sure the cables, terminals and grounds are clean and tight.

The fuel system started with the Lift Pump which is controlled by Oil Pressure Sensor.
Make sure that the Lift Pump is not reverse when PO replace it.
Once you are sure, then you have to test the LP by putting 12V source into it and see if it is pumping by opening the fuel drain valve (I assume it is similar to 95).
If yes, then you need to make sure that the OPS is working. Hook it up to the OPS, crank it with pause to cool starter.
See if it can catch, if not, there is a chance that OPS is bad.
Replace with ACDelco OPS only (usually not available from local part store) so you have to wait to buy it online.

Go from there.
 
Ok typing while putting baby to sleep.
Update. Lift pump is not on backwards, batteries have been load tested separately too they both passed. RECHECKED glow plugs everyone comes out nice and smooth, is intact. Slightly dirty but definitely have some life left in them (they will be changed soon). It has about a half tank of diesel and it is fresh. (Dropped tank emptied and started fresh just to be safe) will go take a video as soon as baby is asleep. Will also be checking ops too
 
The only way to test glowplugs is power them up where you can see them glow red.
GM lists an ohm test- but I have seen bad plugs test good and good plugs test bad.
so remove and power up is only reliable way.
 
I would suggest waiting until you change all the glow plugs . Pull them all out and then crank the engine over . This gives you a much faster cranking speed which helps to bleed the fuel system quicker . You can sit in the truck and see the misting when cranking , it is very obvious . Also , leave all the injector lines connected and tight .
 
I would suggest waiting until you change all the glow plugs . Pull them all out and then crank the engine over . This gives you a much faster cranking speed which helps to bleed the fuel system quicker . You can sit in the truck and see the misting when cranking , it is very obvious . Also , leave all the injector lines connected and tight .

YES!! Do this.

I do this when I build an engine or install new ip, idk why I didn’t think of that.
 
Back
Top