1HDT injection pump resealed and major issues (1 Viewer)

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Joined
Dec 14, 2010
Threads
72
Messages
330
Location
Port Coquitlam, BC
92 HDJ81 275K.

Got my pump back from Okanagan Diesel, reinstalled (doesn't leak one bit, woohoo!), lined up the hash marks on the pump and timing cover (replace the timing belt as well, all went good there). Fired her up, and this is what I'm working with: plumes of white/grey smoke, and a really hard chug at idle - kinda sounds like one cylinder/injector. Video starts with truck at 1200rpm, once I drop it to 550rpm (I know its low, I was tinkering) it chugs really bad like a cylinder/injector in mis firing or clogged. But, as I rev it up it clears up. Then comes back. This happens no matter what the idle is at 500-900 rpm.

Took it for a rip around the block, the smoke went away somewhat (I did replace the fuel filter and filled it with lubrimoly diesel purge, that may be the white smoke) but still chugged.

Went to turn the ignition off, and the key came out but engine kept running for 5-10 seconds until it starved itself. Went to turn it back on and the engine is locked up.

I'm thinking - leaky/malfuctioning injector stayed open causing the late shutdown, then filled the cylinder with diesel, now its hydrolocked.

Next plan of attack - pull the glowplugs and injectors, turn engine over by hand, get the diesel out of the cylinders, reassemble, try and restart.

But what would be causing the chug and white smoke? Is an injector(s) toast? Or could this be a pump issue?

Your thoughts? Feel free to shoot down any and all of my theories, I'm learning as we go here. Steve at EBI has been a world of help along the way, I highly recommend his shop and services. But I got a loaner car for the wife, so I'm going to tinker a little more on this until I completely throw in the towel.

 
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How did you set timing?
Lining up the marks on the pump and timing cover should get you through the gate of the ball park, but maybe not on the field.
You really need to use dial indicator to set the timing.
White smoke, rough idle, rough running suggests timing is way off
 
If it wasn't doing that before, it would be an incredible coincidence for an injector to go bad while the pump was out.
Have you double checked the timing belt, because it sounds like its 1 or 2 teeth out.
But after listening to the video it sounds like its running on 5 cyls. You could loosen the injector lines one at a time. The one that makes no difference will be the cyl not getting fuel.

Have you seen diesel coming from all 6 injector lines?

If it was running ok before the pump rebuild it will be something simple at your end, or a big problem for the people that rebuilt the pump because it should go back to them( if its not something you have done).

Next time ,leave the lubrimolly and filters alone until its running right, it only confuses the issue.
Another course of action would be to attach a clear line into the fuel supply from filter to pump and look for air bubbles.
 
Thanks @Locked79, I'll give that a try.

@mudgudgeon To set the timing I did only line up the marks. I was told it would get me running, but then it would need further tinkering, I guess I thought it would get me closer than where I am, considering the marks are exactly where they were when I took the pump off. I will get my hands on a dial indicator and go from there.
 
@roscoFJ73, it was running perfectly before I took the pump out, just leaking really bad, and losing some serious fuel economy. We're talking a solid drip on the ground every 2-3 seconds while running, and the ACSD was already deleted. You know that saying about leaving bread crumbs to see your path? Well I left rainbow drops of diesel on the wet Vancouver roads.

I will check double check the timing belt as a precaution.

I did see diesel coming from all 6 injector lines, and did crack them on the engine to check. But I will double check.

I've been in touch with the tech who did the re-seal, and he's perplexed as well. But, if it is a pump problem he said he'd fix me up. That means I need to pull the pump and send it to them again though...

Here's hoping I can fix it here.
 
I was told it would get me running

Correct, and it has.

I found when setting the timing with a dial indicator, when rotating the IP to go from the minimum, to maximum plunger lift measurement, the timing marks on the housings were still more or less lined up.

I scribed a line across the housings, and was surprised at how little movement it takes to alter timing

Start with a dial gauge to set timing, and check some basics as Rosco suggests
 
I've been in touch with the tech who did the re-seal

Ask him if he bench tested it before he sent it to you.
It looks like timing or air in the system.
Did the pump get any new parts other than gaskets? If it had new parts that increase the pressure, it could be causing problems with a soft injector spring.

Did you put new injector seats or gaskets in?
 
@roscoFJ73 I did ask him, and he said he did in fact bench test it. No new parts other than seals, gaskets and a few washers.

I haven’t touched the injectors yet.
 
I'm concerned with your theory that the engine has hydrolocked, if that's the case you don't want to be cranking it over until you can clear the fluid in the cylinder or you'll bend a rod or something.

If that ends up not being the case, I'd double check the timing belt marks. If that checks out, cracking the lines one by one to identify the cylinder that's stumbling would be my next step, if you can confirm all lines are getting fuel but the stumble remains you could try switching injectors from cylinder to cylinder and see if the stumble follows, you should probably have new injector seals for this process.
 
@IanB thanks. The plan is pull the glowplugs and see if any fluid comes out. Then, slowly turn the engine over by hand via the crank pulley and bar and push any fluid out. If theres any major resistance I will stop and investigate further.

Thanks for the other tips.

Probably not going to tear into it until after Easter as a diesel mechanic pal of mine can help me then. But I will keep everyone posted. Thanks for all the advice.
 
Ok guys, good news. It's all fixed! Turns out when you switch the boost vacuum hose with a fuel return hose, problems arise. The small hose goes on top of the pump diaphram, the larger hose with the clamp goes on the fuel return outlet off the pump. This is probably a mistake due to working on the truck until 330am one night.

Anyways, we swapped those hoses then tackled the locked engine. Pulled the glowplugs, turned the engine over by hand and fuel gushed, and I mean GUSHED out of 3 cylinders in their own time. Put the plugs back in, aligned the pump and away we went. Checked all the lines and injector nuts too, everything was A-OK.

Plumes of white smoke for a block or two until everything cleared out, but after that, all good. Runs great, adjusted the idle and we're back on the road.

Thanks everyone for the advice and tips, it really helped during my time of duress and absolute panic. I'm trying to post pictures but it looks like I need to host them on another site first. I'll see if I can figure this out.
 
Good news. Ive never heard of that happening before. So basically your fuel return was pumping diesel in via the inlet manifold?
I can upload pics from my files and with 277 posts, so should you
 
Ok I think I did this right.

Yep, @roscoFJ73 I'm pretty sure that's what was happening. Flooding all the cylinders via the intake inlet because I had the fuel return line pumping fuel through there. Where, normally, that hose pulls boost pressure and pushes on the diaphragm to add more fuel in the pump. Correct me if I'm wrong.
hoses.jpg
 
There is a lot of fuel coming out of the fuel return. The feed pump draws in far more than the engine needs and uses the excess to cool the pump which is returned to the tank.
 
Good to hear you figured it out.
That could have gotten very bad very quickly

Honestly never seen that before,
I was almost at a loss to how it hydraulic'd
 
Wow! Good result.
Good call on pulling glow plugs.
Such a simple mistake, could have been far worse.
 
Holy crap. Must be a pretty tough bottom end to take that much hydro-locking without breaking anything.
 

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