Replacing head gasket

[Doubletrouble]

 You mention the rear cylinders if the engine were cold. I couldn't help but notice when I did my injectors that the 3 line closest to the block on the vp44 were the 3 rear cylinders. 

 For the vp44 exberts here, could the vp44 have failed in a way to only supply pressure to essentially one side on the output lines on the high pressure side?

 He may be getting fuel at all lines but not enough to overcome pop pressure to fire the injectors.

[Mopar1973Man]

3 cylinder high idle runs on 4, 5, and 6. 1, 2, and 3 are dead. It fires every other in order. 1, 5, 3, 6, 2, 4

 

Inside injector lines is 3, 5, 6

Outside injectors lines 1, 2, 4

[Tractorman]

11 hours ago, Tex_usa said:

I started with cylinder #1 and losend the fuel line and it shut off right away. 

 

After that I did the same thing with cylinder #3 and #4.

#3 the truck would die but #4 nothing changed.

 

Just curious, you didn't mention checking cylinder # 2, #5 and #6 - did you check them?  Or, maybe you did check them and just didn't post the results.  

 

Checking all cylinders by loosening the fuel line and then documenting the results would be more conclusive than just checking some of them.  The more specific relevant information you provide will likely lead to resolving the problem sooner.   I have mentioned performing this test on all six cylinders in a previous post, but I have not seen any posts from you stating that you performed the complete test.

 

If you did check all of the cylinders, let us know what the results were.

 

- John

[Tex_usa]

@Tractorman no I was not able to get to the other 3 as I ran out of time (3 hr just to do what I did). I will losen #4 and #5 but I didnt think it was worth it since they were cold anyway even after running. #2 I don't know how to get to that one without taking the air horn off? The wrench I have is not small enough to fit with the air horn in place. I could take everything off losen it then put the air horn back and see if it will start?

 

@Mopar1973Man would the best swap be #3 to #6? To try and keep it running and then see if it is the injectors?

#1 and #3 are for sure working so I am trying to figure out the firing order to keep the engine running if it is only those 2 injectors that are working.

[Mopar1973Man]

1,5, 3, 6, 2, 4 is the firing order

 

You'll need at least three injectors to keep it running. So look at it this way...

 

1 5 3 6 2 4

 

Crack the bold try a test then crack only the normal numbers and try a test. You hit in groups of three.

[Tex_usa]

@Mopar1973Man so I have to have 3 for the engine to be running?

Since I know #1 and #3 if loosened kill the engine then it must be the first 3 that are working.

 

Will a vp44 only let the first 3 work if it is failing?

I'm sorry I didn't get out there today but I will try some time this week or weekend and test the other 3 lines.

[Mopar1973Man]

When 3 cylinder high is running 4, 5, 6 are pumping fuel 1, 2, and 3 are dead. You can reverse this to test the others. Might have to raise the idle enough to keep it running.

[Tex_usa]

@Mopar1973Man I did have another question. I'm gearing up to go mess with it again this weekend and was wondering how much of a spray should I be getting when cracking the injectors? I'm trying to rule out the possibility of the vp44 being bad. I am also going to try running a constant hot to the vp to make sure it's not the ecm.

[Mopar1973Man]

You could jump the fuel pump relay to supply power to the VP44. Hard to tell really some just seems to ooze and others will spray the hood. 

[wil440]

8 hours ago, Mopar1973Man said:

Hard to tell really some just seems to ooze and others will spray the hood.

That would really depend on the gap the fuel can get out of

Look at it this way, take some injector line nuts off of the injector/crossover tube and the end of the line will spring or move away from it's tapered seat, some on the other hand will stay where they are and quite tight too needing a slight tweek to get the line out.

Now slightly slacken a line nut off to bleed and some lines move away some don't, the ones that move away will dribble, the ones that stay tight on the seat will spray and everything inbetween.

Slackening lines to test a VP isn't really conclusive because of this variable, all you can hope to see is fuel at every line, one of the only ways to be sure, and for the record I would not even think about doing this is a made up line and a spare injector, the made up line gets the injector out of the engine for observation, I've seen people do this, you would want the injector in a clear container of some sort as fuel spray out of an injector is dangerous to say the least, As i've said I would not even think about doing this

The other way is similar but without the injector and cc what is delivered on each cylinder, this is difficult due to each needs the same amount of time (this is part of a fuel pump test on the test bench)

 

[Tex_usa]

@wil440 that is what I was afraid of. I appreciate the thoughts on this.

 

It ended up raining this past weekend so i didnt make it out to the truck. I did end up just buying a new set of injectors as it was only $525 for a full set from DAP including the core charge. I also picked up some new cummins crossover tubes from a reseller on ebay. 

 

If they are in before the weekend I will try swapping all the injectors and see what happens.

 

After that if it still doesn't work I guess my next best option is to try the injection pump.

[Tex_usa]

Ok guys finally got back out and installed new injectors, recharged the batteries, and ran some tests on the vp44.

 

After installing the new injectors I was having difficulty getting the engine to start again. (Before is was running but just on 3 cylinders)

 

After going through the blue diesel guide on electrical issues with a vp44 I got to the hot wire step. (So far everything else was coming back as it should)

Once I ran the wires directly to the battery I was finally able to get it to start but it would only stay running for a little while and only on the first 3 cylinders.

 

I ended up disconnecting then hot wires and plugging the harness back in and it would still start and stay running but still on only the first 3 cylinders.

 

My question is, does this sound like the vp44 is needing to be replaced?

 

I have checked compression and all 6 are good. I just replaced all 6 injectors as well. And then I just verified that there are not shorts or ground issues with the hot wire test. I'm some what running out of options in my mind but I want to make sure I am not missing something.

 

Any thoughts would be appreciated!

Edited June 12, 2022 by Tex_usa

[Tractorman]

9 hours ago, Tex_usa said:

I ended up disconnecting then hot wires and plugging the harness back in and it would still start and stay running but still on only the first 3 cylinders.

 

My question is, does this sound like the vp44 is needing to be replaced?

 

I have checked compression and all 6 are good. I just replaced all 6 injectors as well. And then I just verified that there are not shorts or ground issues with the hot wire test. I'm some what running out of options in my mind but I want to make sure I am not missing something.

 

I went back and reread this thread (twice now).  From what I understand, this engine was running fine before the head replacement.  You have done many things to diagnose this problem, like removing and re-installing injectors many times.  From my own personal experience I have found that I have caused a problem that didn't exist before I started a repair.  When this happens, I go through all of the possible things that I could have done to cause this.  I also repeat fundamental steps of troubleshooting in order to isolate or prove that what I conclude is true.  If your engine was running okay before you started this project, then it would be highly unlikely (possible, but highly unlikely) that one-half of the VP44 would just quit working when your repair was completed.  So, with that in mind:

 

  *  Could it be that a rag got left in the intake manifold that could be not allowing air to enter the last three cylinders?  How about a rag in the exhaust manifold?

 

At this point I recommend (as I recommended earlier) since the engine does run, perform the injector isolation test for each and every cylinder to prove for absolute certainty which cylinders are contributing and which cylinders are not.  Either get a wrench or make a wrench that will allow you to loosen each injector line one at a time at the head.

 

- John

 

 

[Mopar1973Man]

Injection pump either work or don't. Not just 3 cylinders only. The only way to run on 3 cylinders is 3 cylinder high idle but typically only the rear 3 cylinders. Since only the first 3 are running I would pull all injectors and be pop tested. I've seen new injectors fail either pop pressure fell low or the nozzle cracks. This could be the issue since the VP44 is pump it just means the injectors are not firing because of mechanical issues. If it was me I would pull a 6 injectors and do a compression test on all 6 cylinders being bad rings or cylinder issues could prevent good ignition quality. I've seen members with a cracked piston pass a blow by test. So the only good way to test is compression. Yeah its common for the rear cylinders to take damage being 4, 5, and 6 are hotter than 1, 2, and 3.

[Tex_usa]

@Tractorman I did do an isolated test on the injectors. 1, 2, and 3 are the only ones that are working. 4, 5, and 6 do not change anything when I losen them while the truck is running.

I do have a snake camrea that i could run in all the intake and exhaust to see if I left something. I was worried that maybe I left one in one of the cylinders as it was really late when i put the head back on but i did not think about the air intake. @Mopar1973Man I did run a compression test on each cylinder. All of them came back right around 450 psi. But I did not do a leak down test. Is this what you are talking about?

[wil440]

I haven't got access to much info being on the road in Germany but how do the cylinders and the vp work as in pumping elements, I remember @Tractormanstarting a thread with a lot of info on how the vp works, I  very much doubt it would be 3 injectors as in 1 2 and 3 that's just too much of a coincidence 

Sorry wrong way round 123 working 456 not 

[Tractorman]

35 minutes ago, Tex_usa said:

 I did do an isolated test on the injectors. 1, 2, and 3 are the only ones that are working. 4, 5, and 6 do not change anything when I losen them while the truck is running.

 

Good.  That is important to know.  I don't think you have an injector problem since you have put good working injectors into cylinders that are not firing and you have seen no change in operation.  

 

Viewing the diagram below I cannot see how the VP44 could fail in a manner to lose the three back cylinders on the engine.  It doesn't mean it is not possible, it's just that I don't see it.

 

- John

 

[Tractorman]

On 9/4/2021 at 9:52 PM, Tex_usa said:

After cranking for another 15 min I finally tried to spray some ether and it would fire up as long as I sprayed the ether but as soon as I stopped it would die again.

 

When the engine did start, did it sound like it was firing evenly on all cylinders?  If it did, then you definitely have a fuel problem.  If it sound rough, it would mean that you have a mechanical problem.  It might be worth it to run the ether test again. 

 

I would disconnect the grid heaters, remove the fuel pump relay in the PDC,  and slide back the boot on the intake (driver side) to supply the ether.  Applying the ether here will reduce the distance to the cylinders for the ether to travel.  If there is no blockage in the intake and exhaust manifold, and the engine is mechanically sound, the engine should start and run smoothly on the ether.  

 

- John

[IBMobile]

Maybe I missed this but are you getting fuel out of the lines 4,5, and 6? and how much?

[wil440]

8 hours ago, Tractorman said:

 

Good.  That is important to know.  I don't think you have an injector problem since you have put good working injectors into cylinders that are not firing and you have seen no change in operation.  

 

Viewing the diagram below I cannot see how the VP44 could fail in a manner to lose the three back cylinders on the engine.  It doesn't mean it is not possible, it's just that I don't see it.

 

- John

 

Looking at the picture the only thing I can see that could drop the rear 3 cylinders is if every other ramp on the cam ring was  worn that bad the pressure created couldn't pop injectors but that's about as likely as finding green cheese on the moon, I suppose the delivery pathways in the pump to those 3 injectors could be blocked.  I'd take all six injector lines off and see what fuel is being delivered from the pump then if that's good check what's delivered at injector end of lines,  if that's good then rocker cover off and check cross over tubes aren't leaking then swap 123 injectors into 456 cylinders and see if the problem moves