New to Cummins, Possible Dead Oil Pump?
 

To make a long story short, my friend bent the frame on his '93 D350, so I bought the drivetrain from him and swapped it into my '88 Suburban. His truck had 300k+ miles on it, and never gave him any problems (besides the injection pump that he just replaced with a brand new one), but after I put 180 miles on it in my Suburban, I noticed that my oil pressure had dropped to 0. In a moment of stupidity, I assumed that since the engine had always had good oil pressure, the brand new aftermarket gauge must have failed, so I drive the short ways back to my dorm and investigate it there.

Well, after maybe 5 more minutes of driving, the truck started blowing black smoke and stopped accelerating. I limped it off the road and into a parking lot, and it made a pretty nasty clunk sound and shut off. I pulled the filter and noticed that the turbo is shot (excessive side-to-side shaft play and scoring marks on the compressor housing), and it definitely wasn't like that before. It also makes a pretty bad noise when you crank it, so I haven't tried to restart it.

I got it towed back to campus and haven't had a chance to mess with it since then, but I'd like to get it fixed soon since its my only means of transportation. My first thought is that the oil pump went out, and the lack of pressure caused the bearings in the turbo to die. But, I'm very new to diesels, so I'd love some input from more experienced on what I should do next. Mainly, what would be the best way to go about checking if the oil pump is still good?

Thanks.

If a lack of oil pressure did in your turbo, I hate to think of what it did to the engine.
Dump your oil into a clean container and look for metal.

The engine oil pump is of the positive-displacement design. That being two gears meshed, rotating in what might be viewed as a figure-eight shaped enclosure. The oil moves about in the spaces between the gear teeth from one side of the mesh, to the other.

Attachment 40123



In the Cummins 5.9 12v, oil pump is gear driven.



The bottom line is, you'll have to work really hard to screw it up. Are you sure you even have any oil?

Ive broke an oil pump on my truck. The idle gear broke off. $70 from cummins.

I can't exactly drain the oil since I live in a dorm and only have the parking lot to wrench in. I don't think they would like it if I poured oil all over the lot, and I don't have a container big enough to hold all that oil.

However, I do know that there is enough oil in it, because I changed it when I put the engine in and I checked it after all of this happened. I didn't see anything on the dipstick, and the oil looked/smelled good. I was thinking of pulling the KSB wire and the oil line going to the turbo and then cranking it and look at the flow, but that wouldn't rule out a blockage in that line. Any other ideas on what I can do?

Get some of your buddies to help you jack it up, set it on stands then drain it. You really need to look at your oil, check for metal bits/shavings (hopefully nothing but preferably shavings, not bits). I noticed you didn't list out any mods, is it still a stock motor? Had this happen to a buddy of mine but his turbo blew cause he over-boosted it, like a DA! I doubt that's your situation but we need all the info you got bud.

As far as I know, the motor is all stock, and I was cruising at like 55-60 when the oil pressure dropped. I'll see what I can do about draining the oil and report back.

Sorry for the delay, I've been crazy busy with school. Anyways, I pulled the drain plug today and this is what I found:

http://a6.sphotos.ak.fbcdn.net/hphot...56241150_n.jpg

There were also some shavings in the oil.

Is that the only metal (:jump:) or does the oil look like metallic paint :scare2:

Unless, I'm mistaken, both the Babbit and Copper substrate of the bearing assemblies are not ferrous and won't stick to a magnet. :pca1:

and well make the oil look like metallic paint

New to Cummins, Possible Dead Oil Pump?
 

Cam bearings are made out of much harder material than the journal bearings. Could be cam bearing material or a full on failed journal bearing. Either one will cause a major oil pressure drop.


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Oil did not look like metallic paint, it looked like normal used oil with a couple metallic specks here and there (but not many). Think something could have failed behind the front cover?

:humm: KDP took out oil pump gear possibly :scare2:

X2 tiremann9669

Lets hope you get lucky and it is just the oil pump. go fishing in the old oil with a magnet and see if you get an more metal out of it.

I went through the rest of the oil with a magnet and just got a few more tiny specs, no chunks or anything. And I literally did the KDP fix less than 200 miles ago and loctited the bolt in, plus it was nowhere near out when I checked. Maybe something else came out behind the cover? I need to find a spot other than the parking lot that I can wrench on it, so I can take the front end apart to the point where I can easily remove the front cover.

Did you loctite all of the case bolts ? :c:

I don't like the looks of that drain plug at all. I'm thinking top-end issues, based on the way it went down.

The only bolt behind the front cover that came out was the one for the KDP fix and it got loctited.

What makes you think it was something in the top end? I feel like the oil pump had to have failed to start it all, since the first symptom of something wrong was my oil pressure disappearing.

Here's How I See It
 

From what you stated originally:

Engine had 300k miles. Maintenance history? Valve adjustments?
Turbo blew. Oil pressure went right along with it, since there is no longer any resistance to flow through the turbo feed.
KDP was already fixed, so what makes the clunk in an engine like that?
Something came apart, most likely dropped a valve or 2, would be my guess.

Like was asked before: Where does the ferrous wear metal come from?

Not sure on the maintenance history, but I can find out from my friend.

I didn't think blowing the turbo would drop oil pressure to absolutely zero. When the turbo blew on my CRX, it still had decent oil pressure.

I guess it could be a top end issue, not something I'd thought of before. Is there any easy way to check that on these? Normally I'd just pull the spark plugs and take a look around, can't really do that here though haha.

Pretty easy to look at the valves. There's only one bolt holding each valve cover on.

How do you know the oil pressure went to zero? If you were looking at a gauge tapped into the top of the oil filter where the turbo feed comes from it may have read zero there and still been good everywhere else.

Like BC said, you have to work pretty hard to screw up the oil pump on these engines.

My sender is where the stock oil pressure send was, so if I don't have pressure in the main galley, I'm pretty sure there isn't any anywhere. And I did randomly pull a couple of the valve covers, didn't see anything wrong. I'll pull them all next time I get some free time, maybe I'll see something. Thanks for the advice.

Slight update, I've finally got a place to work on this and it's getting towed there tomorrow. I've also been shopping around for replacement turbos. Should I get another H1C, a high mileage HX35 for cheap, or an H1E? I'm not too up on turbos for big engines like these, nor do I know differences in Holsets that well.

I would find out whats wrong first before shopping a turbo... It might be the least you issues.

I'm betting case bolt or top end issue as well...

If I was replacing the turbo on my 1st Gen I'd use an HE351CW like found on the last of 5.9 commonrails:

eBay - HE351CW

Used turbos are a crapshoot. Lost of people trying to unload junk turbos on eBay, etc. I wouldn't recommend that except possibly from a known good source, like a friend who can truthfully verify the mileage and condition of it.

it could be the turbo was making all that noise when it blew. lost pressure there and showed that on the guage. if u plan on fixing the truck even if its got a blown motor then go ahead and get a better turbo on there and check it out. that drain plug has a lot of material on it but looks like its all somewhat normal material just a lot of it so keep your fingers crossed and bolt on a massize turbo :jump:
on the kdp did you look at all the bolts behind the cover? i cant remember what they go into but there are a few behind the gears that work themselfs loose and can be just as bad as the kdp coming out.

I realize that I should find the actual issue before I start buying stuff like a replacement turbo, but I'm also on a really tight time schedule here so I wanna get all of the variables figured out as soon as I can.

As nice as that HE351CW looks, that's a little over twice what my turbo budget is at the moment.

When I did the KDP, I really didn't look at all the rest of the bolts. Now that the truck is inside somewhere that I can work on it, I'll be able to pull the front cover and see what actually happened. I'm gonna pull the valve covers, too. I should be able to do that sometime this week, so I'll keep this updated.

If you have a toasted motor you schedule is gonna be shot. You really need to find whats wrong first. I have a feeling your gonna have plenty of time to find and order a turbo.

I had a couple hours free today to wrench on it and I was able to get a ton done. I pulled all of the valve covers and found no signs of any top end damage. I removed the turbo while I was waiting for the radiator to drain, and once the radiator was out I was able to pull the front cover. As soon as the cover came off, this fell out:

http://a5.sphotos.ak.fbcdn.net/hphot...5_347499_n.jpg

Just as I had thought, a bolt contacted one of the pump gears and set it askew. As such, gear that does the pumping of the oil wasn't spinning, which explains my lack of oil pressure. Here's what the oil pump looked like after I pulled the four bolts that hold it in:

http://a2.sphotos.ak.fbcdn.net/hphot...97780603_n.jpg

Miraculously, nothing else inside of the front cover was damaged. I'm thinking I got super lucky on this one, but there's still one loose end: I have no idea where that bolt came from. Even with the radiator pulled, there's still not a ton of room to see in there. I looked around for quite a while, and I can't find a hole that's missing a bolt. Its definitely not the KDP bolt, because that one's still there. Any ideas?

There's one behind the cam gear, but I thought that was the only one that could not come all way out by itself. :humm:

Well I figured out where the bolt came from. It was directly above the oil pump. I couldn't see the hole before, but after looking at diagrams, I realized there was a hole there.

Next goal: see if my turbo is rebuildable or not. I forgot my wrench set in my dorm today otherwise I would have gotten it apart while I was there.

That really is too bad. Sorry to hear this happening to anyone but the upside is that your motor may be fine. Was that a bolt location that was visible enough to be seen and tightened when the cover was off during the KDP job? If so, I bet it is one that is never checked by most people when tabbing their KDP.

It was visible when I did the KDP, but I didn't even think to check if it was loose because the KDP bolt was tight.

And yes, here's to hoping that the rest of the motor is okay. My oil pump came in this weekend, so really the only thing left is putting things back together and dealing with the turbo.

I bet that engine is fried,drove to far w/o oil pressure. I would pull the pan and a rod cap see how it goes from there.

With how this swap is setup, the oil pan can't be pulled without pulling the engine, otherwise that would have been my first step.

I had my oil pump crack in half like yours while i was driving on the freeway. I shut it off as soon as i noticed the light was on and towed it home. Put a new pump on it, and it was fine.

That is exactly what I should have done. I'm still regretting assuming that my gauge just stopped working.

I run the stock gauge and an aftermarket gauge tapped into the filter head - different parts of the oil system on opposite sides of the block. If they both drop, there will be no doubt something's gone terribly wrong.

There's no way I could have kept the stock gauge with my current gauge setup:

Attachment 39782

However, the stock Chevy oil pressure gauge was unreliable at best, so its not a big loss for me.