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Knock knock. Who's there?

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The answer to that little riddle would be spun crank bearings. Every single one except the #5 bearing in the thrust cap. 

 

Now the for the back story. 2012 F250, came in knocking like mad, running rough, low oil pressure warning present with engine running. It would run for a few minutes then sputter and stall out. Cyl 5+8 contribution codes, cyl 5 misfire code. Oddly power balance did not show any cylinders dropping out, and relative compression showed only a 3% variation on cyl 7. I did do a manual comp test. Can't remember the results, as I'm not at work, but all cylinders were at or above the 300 psi spec. So at this point I didn't think it swallowed a valve.  Oil pressure was 20 psi at idle, and 35 psi at 2K RPM, this was all with EOT at 55F. I couldn't keep it running long enough to hit operating temp, and honestly I didn't really want to. Also, it was -20F the day I brought it in. The pressures were with in book spec, which seems quite low for me. Dropped the oil pan before I pulled the cab and engine and found this:

 

IMG_20140110_163247.jpg  

 

Further tear down revealed the bearing failures. The picture doesn't show it well, and I'll add one tomorrow, but the sides of the bearing were, for lack of a better word, folded over:

 

IMG_20140113_141434.jpg

 

Notice where the seam between the bearings is located. This is how they were when I pulled the cap, and I could also grab them and spin them around the crank with the cap off. 

 

IMG_20140114_071744.jpg

 

A shot of the crank with the bottom bearing removed

 

.IMG_20140114_072001.jpg

 

I also found this present on the bank 1 head, and in cylinder 1+2 pistons.

 

IMG_20140114_072228.jpg

IMG_20140113_141623.jpg

 

I saw that and immediately thought "That's coolant residue" followed by "Where the hell is it coming from?"

 

After I spoke with the hotline they informed that there have been a handful of bearing failures similar to this. They also enlightened me in regards to my mystery coolant residue. The engineer stated that condensation can form in the exhaust manifolds after engine shut down, and given their unique location on this engine, that moisture can drip down into any cylinders with their exhaust valves open. That moisture can track its way to the glow plug tips, collect there and drip onto the pistons. The rust on the manifold provides the orange color of the residue on the head. 

 

That bit of information certainly raised some questions for me, but it does seem to be an explanation. 

 

Sorry if this is long-winded, but my major diesel repairs are few a far between, and this one seems like a nice find to share. Has anyone else encountered this residue presence? Or the seemingly un-explainable bearing failure? 

 

Oh and one last kicker, this truck has only 12,000 miles and 2 oil changes already documented.

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Nice post and pictures! This type of failure is not something we are used to seeing with our (power Stroke) engines.

 

I personally haven't seen either symptom you have discovered here on this engine - just a few valve related failures and one fuel system take out an engine.

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I was also told about the bearing failures by hotline. The last one I did that was totally locked up I inquired to them about a causal part.  They replied back that main bearing failure would be sufficient to get the claim paid.  It was

 

 

Make sure what ever you do if that's an early 11 and you're reusing the heads that you check the exhaust valves very carefully.  Clean them up and look for cracks.  The one I shortblocked got 16 new exhaust valves because 1/3 of the originals had visible hairline cracks. 

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That's kind of what I figured. I knew the valve issue was fairly common, but a bearing failure of this magnitude with such low miles...its a little out of the ordinary.

 

If anyone has done a short block buildup on one these, I'll take any tips or tricks :P . And what's the best gasket kit to have? From my quick look today I guess there's a few to choose from and some are recommended for "in vehicle repair only." I'm not sure what the difference is or if it really matters. I'll hopefully have chance to look into it more tomorrow.

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I was also told about the bearing failures by hotline. The last one I did that was totally locked up I inquired to them about a causal part.  They replied back that main bearing failure would be sufficient to get the claim paid.  It was

They told me the same for causal part.
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B-Rad had a pretty good post on here about building a 6.7 from a shopping cart full of parts because there wasn't an assembly available, if memory serves me rightly.

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Make sure what ever you do if that's an early 11 and you're reusing the heads that you check the exhaust valves very carefully.  Clean them up and look for cracks.  The one I shortblocked got 16 new exhaust valves because 1/3 of the originals had visible hairline cracks.

I haven't yet but I plan on it. Did you remove the valves or were the cracks visible with them installed?
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  Guess what I am doing right now. Your write up is almost the same as the one I am working on now. This 2012 with 20,000 miles  came in with concern of, after remote starting at like -15 to -10  deg. F.  Started to knock  and leaks oil at front seal.

I am ready to take the crank out in the morning. With the caps still bolted in I can spin some of the crank bearings around. Lots of metal in the pan too. There is no endplay but tons of play up and down. The balancer pulley wobbled like crazy when running. It ran but missed on #1 and #5 compression was 200 psi on #1 and #5 all rest were 300 psi. Relative comp had #1,#5 6% low. This one has some odd rust like marks inside the cylinder walls also.

Thanks for the heads up on the valves Matt!

So JSH what did you get approval for?

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Wow I got one that sounds the same, engine will not say running and an oil leak from the front crank seal. Inspected and found lots of metal in the pan. I have another one outside sounding like its heading down the same road, both are 2011's.

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So far its looking like short block only. But I'm going to comb over those valves.

 

No oil leak on mine but I will add that the vacuum pump had completely failed. Customer had mentioned no power assist brakes and loss of 4x4 all on the same morning it started knocking. I'm not even 100% sure what the internals are supposed to look like but I know I just got a handful of broken plastic pieces and some metal shavings when I took the cover off the pump

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I have done 3 now for this failure. All 3 had piston to head contact and recieved long blocks. 2 of them had to have a new HPFP to get them running, not sure why.

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With the heads flipped over on the bench you can see the cracks in the valves if you look very close. I'm not sure when exactly they fixed this issue but the ones I've seen were early 2011s basically all the trucks affected by the long block TSB need checked.

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So far assembly is going along...well. Except for one issue, the RH head gasket is backorderd until damn near eternity February 17th. This is per my parts monger. Apparently there was some sort of design change? I don't know exactly, but I do know that I have a short block installed and half built up and I'm wondering why the hell he didn't know about this earlier. 

 

I don't know what to do. I think he's looked around other dealers for a possible gasket in stock. I'd rather use an "old" part rather than have it down for another month. Any ideas on what I can do with this?

 

 

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Works for Dodge Neon's. :haha2:

It wasn't copper spray. It was some gooey pink shit you sprayed onto the updated MLS type gasket that replaced the original oil leaking composite POS gaskets that paid 4.1 hours warranty time, but could be done in two or less hours back in the day.

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Another tech here in the shop just got one in. After it ran for a few mintues knocking, it locked up. He got the heads off this morning and he has piston contact on the front 2 cylinders, along with a lot of metal in the lower oil pan. It's a 2011 with 16k miles of it. No glow plug codes though :whew:

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  • 2 weeks later...

We have had 3 engines with spun bearings in the last 2 weeks. The tech comments/issues are worry some. The only thing around here that has changed before this bearing dilemma is the continuous extreme cold temps we have been experiencing, now couple that with the instant high idle these engines are subjected to the moment they start may be a factor in so many bottom end failures. Why they programmed the 6.7 not to idle normally for the first 2 min like the 6.0 and 6.4's then ramp up is beyond me

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The one currently in my stall shattered #8 rod, took chunks out of #4 and #8 cylinder walls, and poked 2 holes in the block. Something bounced off the camshaft and left a nice mark. Heads are coming off to inspect.

 

Update, #8 piston siezed in cylinder. 12 bent exhaust pushrods, 2 broken rocker arm mounts, exhaust valve contact on all pistons.

 

Long block time. Now to inspect the fuel system for contamination.

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  • 4 weeks later...

Had a 2012 limo bus with around 26000 miles (in less than 6 months) with bearing failure like this, had to pull the engine out the front....

 

Boy I don't miss these things :grin:

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