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DFBrews
08-06-2011, 22:39
this is from an 15 liter Cummins that hit 2900 rpm the red line on these is 2100

This truck also DROVE into the shop like this how it did not throw a rod thru the block I do not know. estimated repair cost $42k
And that liner is supposed to go all the down to almost where the crank counter weight is in the first pic
enjoy

http://farm7.static.flickr.com/6006/6011891741_1b1499e3f2_z.jpg (http://www.flickr.com/photos/34834090@N02/6011891741/) IMAG0141 (http://www.flickr.com/photos/34834090@N02/6011891741/) by post_james86 (http://www.flickr.com/people/34834090@N02/), on Flickr


http://farm7.static.flickr.com/6004/6011892435_f3c4c4cd56_z.jpg (http://www.flickr.com/photos/34834090@N02/6011892435/) IMAG0142 (http://www.flickr.com/photos/34834090@N02/6011892435/) by post_james86 (http://www.flickr.com/people/34834090@N02/), on Flickr

http://farm7.static.flickr.com/6121/6012440712_5e4db041ed_z.jpg (http://www.flickr.com/photos/34834090@N02/6012440712/)
IMAG0143 (http://www.flickr.com/photos/34834090@N02/6012440712/) by post_james86 (http://www.flickr.com/people/34834090@N02/), on Flickr

http://farm7.static.flickr.com/6008/6012441406_07ba513c7b_z.jpg (http://www.flickr.com/photos/34834090@N02/6012441406/)
IMAG0144 (http://www.flickr.com/photos/34834090@N02/6012441406/) by post_james86 (http://www.flickr.com/people/34834090@N02/), on Flickr

http://farm7.static.flickr.com/6149/6012442102_aa77877e79_z.jpg (http://www.flickr.com/photos/34834090@N02/6012442102/)
IMAG0145 (http://www.flickr.com/photos/34834090@N02/6012442102/) by post_james86 (http://www.flickr.com/people/34834090@N02/), on Flickr

http://farm7.static.flickr.com/6024/6012442988_8dcff8fc55_z.jpg (http://www.flickr.com/photos/34834090@N02/6012442988/)
IMAG0146 (http://www.flickr.com/photos/34834090@N02/6012442988/) by post_james86 (http://www.flickr.com/people/34834090@N02/), on Flickr

http://farm7.static.flickr.com/6011/6011896115_d461b5e49f_z.jpg (http://www.flickr.com/photos/34834090@N02/6011896115/)
IMAG0148 (http://www.flickr.com/photos/34834090@N02/6011896115/) by post_james86 (http://www.flickr.com/people/34834090@N02/), on Flickr

http://farm7.static.flickr.com/6148/6012444730_9eca0b6f04_z.jpg (http://www.flickr.com/photos/34834090@N02/6012444730/)
IMAG0147 (http://www.flickr.com/photos/34834090@N02/6012444730/) by post_james86 (http://www.flickr.com/people/34834090@N02/), on Flickr

nynco
08-06-2011, 22:42
Wow..... and 42K is insane.

When people F up an engine, why the hell do they insist on driving it to the shop? Get a tow..... it will save money in the long run.

spyder
08-06-2011, 22:51
aw come on, jb weld that shit and put it back together! [Beer][ROFL1]

Hannu
08-06-2011, 23:21
O-ouch...

streetglideok
08-06-2011, 23:32
Somehow, I dont think driving it in did anymore damage then towing it in,lol. What did this guy do to take the engine to 2900rpm? Think its a testament to Cummins, it still ran!

DFBrews
08-06-2011, 23:39
Somehow, I dont think driving it in did anymore damage then towing it in,lol. What did this guy do to take the engine to 2900rpm? Think its a testament to Cummins, it still ran!

the wrist pin was the root cause of failure... started puking oil into the intake and the engine ran away before it f'ed up the piston enough to lose compression.


The thing sounded horrible so close to throwing the rod the bearing cap bolts stretched and the bearing came loose and was hammered flat. and was just spinning in the journal causing even more problems. starving the rod of oil just compounding the issues. A while back we had a Cat engine that drove in with a broken crank.

mcantar18c
08-06-2011, 23:48
I don't know what to say to this, other than I want to see it in person lol.

DFBrews
08-06-2011, 23:50
I don't know what to say to this, other than I want to see it in person lol.

come on down to the shop tomorrow I will be there by 10

mcantar18c
08-07-2011, 00:13
come on down to the shop tomorrow I will be there by 10
I would but unfortunately I have to work [Bang]

nynco
08-07-2011, 00:34
Somehow, I dont think driving it in did anymore damage then towing it in,lol. What did this guy do to take the engine to 2900rpm? Think its a testament to Cummins, it still ran!

One thing I have learned in mechanics. The second you think there is something wrong, stop. Best example is detonation. If you hear it knocking or the computer shows, don't push it, fix it.

If this guy had thrown a wrist pin. Well that is bad news. But driving it longer with all the metal bits crunching through other parts of the engine or the cuts back on the amount of salvageable parts. Who knows, maybe the block could have been saved and just over bored a little. I am not an expert on big engines by any stretch. Just using stuff I have learned from turning wrenches in the past.

rondog
08-07-2011, 00:45
"Here Bubba, hold mah beer. We'll get this sumbitch over the hill".

mcantar18c
08-07-2011, 00:56
One thing I have learned in mechanics. The second you think there is something wrong, stop. Best example is detonation. If you hear it knocking or the computer shows, don't push it, fix it.

If this guy had thrown a wrist pin. Well that is bad news. But driving it longer with all the metal bits crunching through other parts of the engine or the cuts back on the amount of salvageable parts. Who knows, maybe the block could have been saved and just over bored a little. I am not an expert on big engines by any stretch. Just using stuff I have learned from turning wrenches in the past.

I learned the same lessons and came to the opposite conclusions as you (shocker).
If there's internal engine damage, its usually easier and cheaper to simply replace the engine. The last instance I had was with my 79 CJ7. Threw a rod on the highway about 7 miles from home. Pulled over, popped the hood to check it out, decided it was f*cked and said screw it and drove home. It would have cost me hundreds in parts and labor for new pistons and all that goes with them, to have the block machined and bored out, etc. I paid $100 for a complete, running replacement long block, swapped it in, and it was good as new. Then I made $200 off the blown engine between selling good parts and the scrapyard.

nynco
08-07-2011, 01:26
I learned the same lessons and came to the opposite conclusions as you (shocker).
If there's internal engine damage, its usually easier and cheaper to simply replace the engine. The last instance I had was with my 79 CJ7. Threw a rod on the highway about 7 miles from home. Pulled over, popped the hood to check it out, decided it was f*cked and said screw it and drove home. It would have cost me hundreds in parts and labor for new pistons and all that goes with them, to have the block machined and bored out, etc. I paid $100 for a complete, running replacement long block, swapped it in, and it was good as new. Then I made $200 off the blown engine between selling good parts and the scrapyard.


Well, may be true with your engine. Something tells me a new block in that Semi is not so cheap. Blocks are not always cheap nor readily available for all engine types. Esp newer cars. If you got a common car, well that makes life easier. Regardless, you are talking about a thrown rod. When you got metal running all over the wrong places, then you got problems going to all parts of the engine too. Drive it more and perhaps you need a new head too. Pistons banging against a head over and over and over will kill it. Look at the face of the head from constant impact damage. It looks like the guy lucked out and did not bend a valve. I myself would most likely replace those valves on that cylinder to make sure. Drive it more and you could send metal into the oil pump. Lock your oil pump and the whole engine is toast. Stop and you avoid further damage and can salvage more, thus lowering your costs.

nynco
08-07-2011, 01:33
the wrist pin was the root cause of failure... started puking oil into the intake and the engine ran away before it f'ed up the piston enough to lose compression.


The thing sounded horrible so close to throwing the rod the bearing cap bolts stretched and the bearing came loose and was hammered flat. and was just spinning in the journal causing even more problems. starving the rod of oil just compounding the issues. A while back we had a Cat engine that drove in with a broken crank.

DFBrews just said that the wrist pin went bad and driving it more compounded the issues. [Beer]

DfBrews... whats the story on that piston crown. I have never seen a design like that. I am referring to the cone and what looks like a strange internal pocket around that. Is that to create some type of swirl to better the burn?

mcantar18c
08-07-2011, 01:44
Eh, the way I see it... you need to bore the block out anyway, which means machine work + new pistons. If you're doing the machine work on the block you may as well get your head worked over too. Since you're getting new pistons, you'll likely be getting new rods with it and you'll need new bearings with all of this. Also, you may need to machine your crank if it was damaged.
At this point, you may as well throw a whole new engine in there IMO.


DfBrews... whats the story on that piston crown. I have never seen a design like that. I am referring to the cone and what looks like a strange internal pocket around that. Is that to create some type of swirl to better the burn?
Use your google fu. Search for things related to diesels and high-compression racing engines. The information is out there and easily accessible.
Basically, yes, it helps to swirl and mix and compress the air-fuel mixture. It also has to to with the combustion chamber itself, but google will explain all of this to you.

nynco
08-07-2011, 01:48
Eh, the way I see it... you need to bore the block out anyway, which means machine work + new pistons. If you're doing the machine work on the block you may as well get your head worked over too. Since you're getting new pistons, you'll likely be getting new rods with it and you'll need new bearings with all of this. Also, you may need to machine your crank if it was damaged.
At this point, you may as well throw a whole new engine in there IMO.


Use your google fu. Search for things related to diesels and high-compression racing engines. The information is out there and easily accessible.

Is fu. supposed to mean f*ck you?

I have seen high compression pistons just not like that. I am not as familiar with big rig engines nor high performance diesel internals. Forgive me for asking questions so I could learn...

mcantar18c
08-07-2011, 01:54
Is fu. supposed to mean f*ck you?

I have seen high compression pistons just not like that. I am not as familiar with big rig engines nor high performance diesel internals. Forgive me for asking questions so I could learn...

No, google fu like kung fu. As in, a skill or an art form, one that you should have mastered in this day and age. But if you'd like to take it as f*ck you you're more than welcome to.
The reason I told you to google it is that I, and I'm sure the OP is on the same page with me, do not want to explain diesel mechanics to you and everything necessary to give you a full understanding of what you're asking, especially when all of this information is pretty easily accessible.
Here's some links to start you out...
http://www.enginebuildermag.com/Article/1788/diesel_pistons.aspx
http://www.dieselbombers.com/general-diesel-related/54604-evolution-diesel-piston-designs.html
http://saeeng.saejournals.org/content/1/1/913.abstract

Actually, here's a little quote from that first link for ya...

The combustion chamber in most diesel engines is actually in the top of the piston rather than the cylinder head. There is a bowl-shaped recess that swirls and compresses the air as the piston comes up
And another one from the 3rd link... you probably won't understand half of this but it explains the purpose of a bowl/cone... actually it really just talks about the advantages/disadvantages of a small bowl vs a big bowl, but you'll get the idea.

The data show that piston-bowl diameter influences in-cylinder mixing and pollutant formation processes by altering jet-jet and jet-wall interactions. When the fuel jets impinge on the bowl wall prior to ignition, adjacent jets merge, forming fuel-rich regions where soot formation occurs. By using a larger diameter bowl, wall impingement prior to ignition is reduced and delayed, and mixtures are leaner throughout the jet. However, a greater fraction of the jet becomes too lean for complete combustion. By using a smaller diameter bowl, a strong jet-wall interaction pushes the fuel-rich jet-jet interaction regions into the center of the chamber, where mixtures are predominantly lean. This reduces net soot formation and displaces fuel-lean regions of otherwise incomplete combustion into the combusting regions near the bowl wall.

nynco
08-07-2011, 02:09
McCantor, thank you for pointing me in the correct direction in regards to the diesel stuff. I also learned the term google kung fu. So thanks for that too. I will read some of the links over.

nynco
08-07-2011, 02:14
I follow most of it, but the term "jet - jet" is throwing me. Is it referring to dual injectors?

mcantar18c
08-07-2011, 02:14
Atta boy.
Now just one question. How do you manage to spell my name wrong when its written right the f*ck in front of your face?[ROFL1]

nynco
08-07-2011, 02:16
Atta boy.
Now just one question. How do you manage to spell my name wrong when its written right the f*ck in front of your face?[ROFL1]

No insult or disrespect intended, I was going by memory and did not scroll down to get it perfect.

mcantar18c
08-07-2011, 02:17
I follow most of it, but the term "jet - jet" is throwing me. Is it referring to dual injectors?

The way I'm reading it in that article, is "jet-jet" refers to where the jet mixes with itself after bouncing off the bowl (the "jet-wall interaction").

mcantar18c
08-07-2011, 02:17
No insult or disrespect intended, I was going by memory and did not scroll down to get it perfect.

No insult or disrespect taken, just thought it was funny.

nynco
08-07-2011, 02:19
Jet-jet must have something to do with the newer generations of piezo injectors that are pumping out that massive amount of pressure. like some form of blow back hitting the jet stream before the injector closes thus vaporising more. Still guessing though...

jmg8550
08-07-2011, 09:26
Since diesels are direct injected, I believe jet refers to the high pressure fuel stream entering the combustion chamber. Seems what they are talking about is how the bowl in the piston creates lean and rich pockets. Soot control is affected based on the design of the bowl ie. large or small bowl. The fuel injector has nothing to do with pressure, it is simply a valve and a nozzle. The injection pump and computer (modern diesel) are what controls pressure.

Diesels are compression combustion engines, no spark plugs. The mixture needs heat to ignite, that is where compression comes into play. It creates the heat necessary to ignite the mixture. If the jet of fuel coming into the chamber is not mixed correctly, it will cause uneven combustion and soot will start to build up on the piston. Also engine efficiency will suffer.

Most diesel engines have oil "jets" spraying the bottom of the piston to keep them cool. Otherwise the piston will melt down, and from what I understand, decrease soot deposits even further on the piston.


Hope this helps.

Graves
08-07-2011, 09:32
$42k?!???! Holy sh*t!! We can get a complete ISX (450) direct from cummins for $21k.

DFBrews
08-07-2011, 10:13
$42k?!???! Holy sh*t!! We can get a complete ISX (450) direct from cummins for $21k.

Was it a regen isx? Think it is about 26k for Reman 18 hrs of tear down at 125 bucks an hour. Plus another 40 hours for a swing needs a dpf and catalyst at 4k radiator because when it let loose it put metal into the cooling system at about 2000 in parts

Graves
08-07-2011, 10:19
Yep, post 07 ISX, usually don't need to worry about tear down when it sounds like that though.

DFBrews
08-07-2011, 10:31
Yep, post 07 ISX, usually don't need to worry about tear down when it sounds like that though.

Hmm now I need to double check the prices

this is a warrenty gig so they wanted it apart for diagnosing the failure. Thought UPS ran those Mack monstrosities

Graves
08-07-2011, 10:52
We still have quite a few Mack's, most of our new(er) stuff has been international's with either the ISX or S60's.

sniper7
08-07-2011, 11:02
You guys should see when one of the engines I drive around fails!

Bailey Guns
08-07-2011, 11:09
You guys should see when one of the engines I drive around fails!

Causes you to use a river as a runway?

Graves
08-07-2011, 11:16
You guys should see when one of the engines I drive around fails!

You'll poop a little.

jmg8550
08-07-2011, 11:18
You guys should see when one of the engines I drive around fails!

[Worth]

Sorry, I just had to.

But please, do tell/show us.

cofi
08-08-2011, 12:59
thatll buff right out :D