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94 2500 6.5 turbo won't start

While you were cranking to get fuel instead of properly bleeding as was suggested you probably sucked air into the Injection pump.
This makes these things hard to start even when they have a clean recent history.
If you keep cranking this thing unnecessarily you're going to kill your starter or at the least it will lead to a premature death.
There is a reason it was suggested you hot wire the lift pump. If you read the stickies about testing the lift pump I'm prettyy sure it doesn't say anything about cranking the engine on an empty filter bowl. Where do you suppose the air from the bowl that didn't come out the bleeder went?
 
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I didn't get the last 4 plugs done before it started raining. I'm going to try to get them done tomorrow and try to bleed the fuel system completely.
 
If you have not done so already it would be a good idea to go to the technical library and read through the whole lift pump troubleshooting thread. the whole thread, at least 3 times so it sinks in. I do not assume anyone really understands how to do these tests until I read them explain it. You will find specific info pertinent to your 94 in later posts of the second page. And people have said it here, just hot wire the LP to make it run for testing. Its real simple on yours with the fuse on the passenger side firewall. And make sure you open the T-valve first, turn it about 5 times.

http://www.thetruckstop.us/forum/sh...t-Pumps-amp-OPS-operation-and-troubleshooting

You can ignore all the stuff about the OPS for now, as it is only needed when the engine is running, and not to start it.

Another method to get it to start if glow plugs are the issue is blow a heat gun/hair dryer into the intake, get warm air into it.

There is a diagnostic checklist that would have you check several things, including if fuel is getting to the injectors. For someone proficient with a multimeter there are more diagnostic techniques for a no-start condition.

Right now it sounds like you have several bad glow plugs, but also don't discount the controller itself, and because these things happen a weak LP as well (these trucks get abused and not maintained). If you have a manual override on the glows do you know how it is wired, is it on its own solenoid or just tap into the existing controllers trigger?

Ways to give you the most cold advance and computer controlled glow time is by unplugging the Coolant Temp Sensor (CTS) on the t-stat xover and the Intake Air Temp (IAT) sensor on top of the intake plenum.
 
Yes, read the threads Buddy has pointed out and while you are checking the glow plug system, ensure you inspect the wire leads at the Glow Plug Controller for connection and corrosion. Might as well go after the GP connections and clean them up at the GP spades and at the controller. If the connections at the GPs are not good and tight, replace them. Mechanics at work (Army...lots of 6.2 and 6.5s) and a friend who's more than proficient on 6.5s all said to get the passenger side plugs swapped out too. They seemed to place a lot of value on the PS side. Figures as it is such a joy to work on.
 
I'm not sure what the drivers side /passenger side relationship would be.

When my daughter etherized our 98 Suburban, there were 2 glow plugs working on the drivers side and only one working on the passenger side.

I also find my long needle nose pliers - bent and straight &/or my smallest long hose pliers come in handy for pulling the glow plug wire and reinstalling them. Especially on the passenger side.

And the cheap pliers from Harbor Freight are my favorites. They aren't as bulky as my Snap-ons and get in tighter places

A $10 wobble extension set from Harbor Freight is also a good investment if you don't have a set yet.

I usually remove the heat shields and reinstall them but I've done the dirty deed while leaving them in place.

Be careful when you get to that point as you do not want to round the heads on the nuts anymore than they are now. Usually if they are deteriorated you can tap a 9/16 socket on them.

I give them a PB Blaster, Kroil or Knocker Loose Bath before I start.

Be careful not to get those products on your plastic down there - wires, looms Or starter. Those products will do a number on plastic. I usually spray down with Simple Green and a plastic friendly lube bricating oil after using PB or similar.

I also spray the area down with Simple Green & keep the bottle full and handy before I put the heat on the nuts - AND ONLY ON THE NUTS.

I almost always heat them & shoot them with Sea Foam or Deep Creep - aerosol Sea Foam - immediately after heating. I try to keep the stream of Sea Foam aimed at the stud and the heatshield right next to the nut.

If you have a better place that you can work available I would try the hair dryer trick to get the truck running and moving.

After you do another lift pump test.

When next you try to start, avoid extended cranking intervals. READ up on this, there is a time limit on how long you should crank the starter per try and then let it cool between tries.

Note how long your glow plug light stays on. It should be about 15 seconds. Bad glow plugs often cause a short cycle.

Did you check for voltage at the spade connectors on each glow plug or with the ampmeter?

You've got half the glow plugs changed but you also want to know that you are getting power to each glow plug.
 
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I hot wired the LP from the fuse and it is running but it sounds pretty sick. The pump almost sounds like a small engine knocking when it runs. I rebled the system right with it hot wired. I don't have access to a pressure gauge so no idea how well it's pumping. I need to get new batts but I won't have the $ till friday.
 
that's how those pumps sound. Let it run into a measured container. IIRC it should fill a 2 liter bottle in about a minute
 
Don't worry about the pump noise. Sounds about normal for these pumps.

How much fuel did you run out of the drain petcock?

Don't worry about the pressure gauge for now. When you opened the drain and timed the flow, How long did it take you to run a quart of fuel into the container?

If your batteries are low that could affect the pumps flow rate.

How are you coming on the glow plugs?
 
jrsavoie said:
I'm not sure what the drivers side /passenger side relationship would be.
Click to expand...

Me ether, er, either. I just noted that they were pretty adamant on the point but perhaps they felt there was a need to get a full set of healthy units in there.

Thanks for the great advice, the specific points on not only what to test and where and what to look for etc. Good lessons for us all.
 
I think they probably realize that people ignore the passenger side because its more difficult to get to, so point being, dont ignore them, test them all and reaplce them all when changing them.
 
One thing I forgot to ever mention was to close the T valve & filter bleeder before stopping the lift pump.

You don't want o risk getting any air in the system by doing the reverse order.
 
First chance I've had to do anything all week. I tested the LP pressure and it's only making about 3-4 psi. It also took it about 40 secs to pump a quart out the t-valve. I'm going to get the GP's done today and try to get the LP replaced as well. Thanks for all the help so far I'll keep you posted.
 
I got the GP's done but ran out of daylight before I could replace the LP. I bled the fuel system twice with the old one so there are absolutely no air bubbles. Still won't fire so I'll do the LP tomorrow and if that don't do it I'm not sure where to go next.
 
Did you test for voltage at each glow plug spade connection?

At this point you do not have to disconnect them But you can if you wish. You can also test for amps around each individual glow plug wire as previously described either here or at the other thread.
You have to test at the glow plugs or you don't know if your new glow plugs are getting juiced.

Do you have any smoke in the exhaust while trying to start?

How many times did you try starting the truck?

Do you have it plugged in?

Did you hot wire the lift pump while trying to start? This can help if you would happen to have any fuel line leaks.

With air in the Injection pump it can take some time to start these. Bleeding won't get air out of the injection pump.

Do you have somebody with a diesel and heavy duty jumpers that can jump start the vehicle? Or a heavy duty booster charger?

I'm not sure what you have available for electricity or tools.

Also you said your have at least one bad battery. These won't start without a good cranking speed. Hence the jumper cables or battery charger. or both.

Is your glow plug light staying on the proper length of time now that you have the new glow plugs installed?

Do you have a manual glow plug overide switch?
 
Are you getting fuel at the injectors? try cracking the 4 inj lines on the driver side and truning it over. if you are getting good fuel it will make a mess if no mess no fuel
 
I would recomend checking for juice at the glow plugs and checking how long the glow plug light stays on. You want at least 15 seconds.
You can try spraying a little Marvel, Wd40, Sea Foam or similar into the intake hose and see if it trys to run at all.
 
I'll try to answer your questions in order jrsavoie=

Did you test for voltage at each glow plug spade connection?
Yes 12v at all 8.

At this point you do not have to disconnect them But you can if you wish. You can also test for amps around each individual glow plug wire as previously described either here or at the other thread.
You have to test at the glow plugs or you don't know if your new glow plugs are getting juiced.
I tested them when I replaced them.

Do you have any smoke in the exhaust while trying to start?
None at all.

How many times did you try starting the truck?
I tried about 4 times cranking for 10-15 secs each and waiting for 3-4 mins in between tries.

Do you have it plugged in?
Yes it had been plugged in for nearly 3 hours and I also waited for the fuel to preheat as well.

Did you hot wire the lift pump while trying to start? This can help if you would happen to have any fuel line leaks.
I'll try that tomorrow when I can get some help.

With air in the Injection pump it can take some time to start these. Bleeding won't get air out of the injection pump.

Do you have somebody with a diesel and heavy duty jumpers that can jump start the vehicle? Or a heavy duty booster charger?
I don't know anyone with a diesel but I've been using my batt charger set to 50 amp fast start.

I'm not sure what you have available for electricity or tools.
I have one extention cord and some basic hand tools. I also just received a pressure gauge (thank you Paul I owe you big).

Also you said your have at least one bad battery. These won't start without a good cranking speed. Hence the jumper cables or battery charger. or both.

Is your glow plug light staying on the proper length of time now that you have the new glow plugs installed?
It's staying lit for about 10-15 secs the first time but after that I have to wait a min or two to get a full cycle.

Do you have a manual glow plug overide switch?
No but I do want to install one. Is there a thread on here about that? What would be the best way to route it?
 
If you had block heater plugged in and got glows going for 10-15 seconds and a lift pumpt at 3psi it should start. Is it even trying to start? Does it crank smooth, or does it stumble or pop or anything? If you arent getting even the hint of combustion then must not have fuel at the injectors, then you will be getting into different troubleshooting. Healthy glows and a healthy LP are necessary for good operation, so no lost effort there. You can try a manual glow over ride or a reprogrammed PCM EPROM can also extend glow time.

To try getting this thing started unplug the CTS on Tstat Xover, IAT sensor on intake, and Optical Sensor (OS) on top of the IP, then crank for about 15 seconds.
 
buddy said:
If you had block heater plugged in and got glows going for 10-15 seconds and a lift pumpt at 3psi it should start. Is it even trying to start? Does it crank smooth, or does it stumble or pop or anything? If you arent getting even the hint of combustion then must not have fuel at the injectors, then you will be getting into different troubleshooting. Healthy glows and a healthy LP are necessary for good operation, so no lost effort there. You can try a manual glow over ride or a reprogrammed PCM EPROM can also extend glow time.

To try getting this thing started unplug the CTS on Tstat Xover, IAT sensor on intake, and Optical Sensor (OS) on top of the IP, then crank for about 15 seconds.
Click to expand...

It's not even trying to start. It spins over and sounds like it has good compression just won't go. It was running fine when I got it so wouldn't the injectors be good(ish)? What if one or two had a slow leak into the cylinder? If so, maybe it's causing it to flood out? I tried unplugging the IAT and CTS and it made no difference. Which one is the OS?
 
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