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dieseldummy
07-25-2005, 15:47
Well, here is the latest aftermath of a poorly designed underbuilt engine... Bent rod, broken crank, busted main webs, and a couple of broken pistons. It's hard to tell which happened first, but I'd venture to guess crank or main webs were first and the rest followed...

Bent Rod:
http://img.photobucket.com/albums/v622/dieseldummy/FXCD0004.jpg

Broken Crankshaft:
http://img.photobucket.com/albums/v622/dieseldummy/FXCD0002.jpg

Main Web:
http://img.photobucket.com/albums/v622/dieseldummy/FXCD0001.jpg

Broken Piston #1:
http://img.photobucket.com/albums/v622/dieseldummy/FXCD0007.jpg

Broken Piston #2:
http://img.photobucket.com/albums/v622/dieseldummy/FXCD0006.jpg

A couple of the pics are kind of crappy, but ya get the idea... This is part of the reason behind my advice to not buy a 6.2/6.5 diesel...
__________________

Chris611
07-26-2005, 03:13
Sorry for you loss. Was you engine stock or were there some modifications? Just curious. Also what do you think caused this? My truck has 131K on it. I don't pull very heavy loads compared to some, but I would like to keep it around for a little longer ;)

Thanks
Chris

dieseldummy
07-26-2005, 19:27
Chris,
Engine was stock compression, but that was about it. Better turbo, different cam, intercooler, cooling mods, ect... Crank most likely let go and took the rest with it, seems to be the popular thing to do.

markrinker
07-26-2005, 19:50
Wow...sorry for the news, DD. What are your plans for the truck?

dieseldummy
07-26-2005, 20:14
Probably a lower budget repower and sell. I can't justify spending more on a pickup that is 12 yrs old with 148K on the odometer. It's kindof funny, the first engine went 115K, the next few averaged 10K or so... I guess I must be super hard on things or something.

Kennedy
07-27-2005, 04:50
Some say that they've seen broken cranks in good blocks, but myself, I've only sen broken cranks in cracked blocks, and plenty of broken blocks with good cranks.

118k for my first one, 6 k (124-ish) later I had the block split again. Now up around 170k+ with no issues.

markrinker
07-27-2005, 07:32
This is why I've decided to put both of my 6.5s into 'semi-retirement', i.e. plowing and landscape duties only. After gleaning ~30K miles on the used motor swapped into #2 last spring, I consider it 'paid for'.

The heavy pulling, long miles and 'daily grind' are now shifted to the newer 6.0 gasser and Duramax.

I hope this strategy keeps the 6.5s around for at least 2-3 more plowing seasons. Pictures like this make my anxiety meter peg, I don't want to drop another motor in either of them. They are excellent plow trucks and move mountains of snow without high RPMs.

My theory is that the block cracking and failed cranks start as casting flaws, but are accelerated by cold starts (thermal expansion) and high RPM operation. I plan to baby both of these older engines by leaving them plugged in at all times during the winter months.

Whitpirate
07-27-2005, 09:09
Sorry for the loss..... I'm getting near your miles and think about this regularly. Are you interested in selling the intercooler if you are just going to repower to stock? I'm interested if you are.

BuffaloGuy
07-27-2005, 11:59
Call Jamie Avant and get a $1700 used motor. That's what I did. So far I am very pleased. I feel your pain.
Ken

markrinker
07-27-2005, 12:34
Wow, only $1700 used? Short block?

tom.mcinerney
07-27-2005, 17:06
Thanks for the great photos , DD.
Very sorry for the subject matter.

More images for the subconscious to mull over while cruising....

RT
07-27-2005, 17:15
Sorry for you loss. OTOH, aren't you the guy running the Holset? With much more boost than stock? Lots of mods to the engine? And you are surprised it went bang with lots of mods of on a stock compression block? Its been proven time and again that stock compression and mods really don't mix well. If you are going to lean on a 6.5 the 18-to-1 pistons are mandatory. The stock or very lightly modded 6.5's seem to last just fine if not abused with max towing efforts. Its a question of pay now, pay later. Let us know when you are gonna sell all those hop-up parts.... RT

dieseldummy
07-27-2005, 19:56
I think these engines are just weak, a shallow skirt design is not the way to go for any kind of diesel engine IMHO. The intercooler is more or less a permanant part of the pickup, I made it special so it required some special placement. I don't think that a $1700 dollar engine is what I was looking for, I think if I put my mind to it I could rebuild an engine for that much if I put my mind to it that is... I've mentioned this in the past and I'll say it again, the head gasket should be the weak point in the chain. I seem to remember something about oddly staggered head bolts being a problem... As far as the parts go I have been talking to someone who has first dibs, but what he doesn't want will be listed in the for sale forum. I think I'm going to try to go the same route as Mark, the rare elusive Duramax will eventually find it's way into my care...

NH2112
07-29-2005, 17:30
Well, they were designed as 130-150hp light-duty engines, when you start approaching double that you can't really be surprised if something lets go.

IMO the biggest problem with the 6.2l/6.5l head bolt arrangement is there are no head bolts between the cylinders. Every other diesel I've worked on (not that I've worked on everything out there) has 6 bolts around each cylinder, the 6.2l/6.5l have only 4. The 6.2l/6.5l could definitely stand to have another 100-150lbs of iron in them, but with that being said they're still pretty robust as long as you don't go nuts with power increases. I'd say that one putting out power similar to the 1st generation 5.9l - 160hp, 400lb-ft - should pretty much run forever. But, everyone today HAS to be able to accelerate up a 6% grade while at max GCWR, so these engines get built way beyond their design limitations.