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Where did that carnage thread go lol

Major bummer, man! At least it got to grace the pages of DieselPower. Definitely curious as to what happened. Rod bolt fatigue, rod saddle fractured, cap fracture, beam fracture?
 
I spy with my little eye, a snapped connecting rod on #8. Crank is oddly just fine, though a small chunk did get taken out of the side of the block. I am going to talk with my engine building and see if we can't sleeve it. I doubt it though.
Starter.jpg ConRod.jpg
 
6.5L said:
I spy with my little eye, a snapped connecting rod on #8. Crank is oddly just fine, though a small chunk did get taken out of the side of the block. I am going to talk with my engine building and see if we can't sleeve it. I doubt it though.
View attachment 49459 View attachment 49460
Click to expand...
Is the rod next to it bent, or is it just the picture making it look funny?
 
Yeah I think the #7 is tweeked as well. Havn't got a good look at it yet. going to pull heads maybe next weekend
 
It ran was still running in still I shut it off. Just shook like a MOFO and sounded nasty. Wouldnt have ran for long with the waterfall of oil coming out from it though. I basically helped latch a piece of the insterstate lol
 
UPDATE: I tore it completely down this weekend. #7 had a small nick out of the bottom of the cylinder and #8 had a larger chunk. I talked to my engine builder who said #8 will have to be sleeved and #7 should be ok as is. Crank and block will get mag-flux'd and mic'd. There was absolutely so sign of anything that would have caused this failure. All bearings, valves, everything was perfect. Even the broken con rod spun freely on crank still. All mains fine. Cylinders still had amazing cross hatching in them for 100K miles. damage.jpg
 
6.5L said:
UPDATE: I tore it completely down this weekend. #7 had a small nick out of the bottom of the cylinder and #8 had a larger chunk. I talked to my engine builder who said #8 will have to be sleeved and #7 should be ok as is. Crank and block will get mag-flux'd and mic'd. There was absolutely so sign of anything that would have caused this failure. All bearings, valves, everything was perfect. Even the broken con rod spun freely on crank still. All mains fine. Cylinders still had amazing cross hatching in them for 100K miles. View attachment 49763
Click to expand...
So is the initial diagnosis hydrolock? Have you done any inspecting of your injectors? It seems hard to believe that a leaking injector could dump enough fluid to hydrolock a cylinder at speed....but what else could it be? Your head gaskets looked ok?
 
I have seen 1 years ago that was defective rod, but I cut it open where it bent and there was an air pocket in the casting of the rod.

Wacky.
 
How did the #7 rod look?

What's the cost to sleeve a block?

At the minimum measure rods and rod bolts for stretch. Myself I would scrap all 8 rods and bolts - just to be sure. Not like # 8 can be reused anyway... :p

I keep thinking of the rare 1962 Olds Jetfire using Turbo Rocket Fluid (one of the first production turbocharged) Oldsmobile engine failure mode. Water/Meth was used to keep knock down with the high compression engine. Completely too complex for your average GM service department esp. in the days before flowcharts... Regardless the systems would leak Turbo Rocket Fluid into the intake with the engine off. On startup the engine would hydro bend a rod and run till you hit about 45 MPH before the rod would break.
 
The rod wasn't bent though then removed. Rod was snapped completely off at the base of the wrist pin and at the base of the connecting rod on the crank. No signs of being bent. I had been driving for probably 20minutes at highway speed (80mph/2700rpm) when it happened. Head gasket was perfect. Not a single sign of failure. I thought my water meth tank was maybe leaking fluid into the intake as well but dismissed it immediately for a few reasons. First, I have a solenoid that remains closed unless it's injecting, placed before it even hits the water meth pump, so the lines should have been dry. 2nd, I had it disabled completely so no power hits my water meth pump, and even if the pump seals failed, it couldn't send it that far up hill on gravity alone, assuming the solenoid had failed as well, and 3rd, I drain my water meth tank every winter, so it's bone dry to begin with. I am going to send my injectors to my fuel guy and have them flow tested and inspected. I find it hard to believe the fuel load was enough to hydro lock it. Also, he has my prototype DB pump, so that will be going on as well then motor goes back together. So no sign of hydrolock. No piston damage at all in any cylinders. The rod had no previous visible sign of stress fractures, but that's just eye inspection. My only theory is that it had always been a defective rod, and finally had checked out. And not sure on cost to sleeve it, but will get done. I got a wicked smart engine guy. The guys been building engines for about 40 years, so I trust him, but he did tell me some interesting things. He talked me out of a gear set for the timing. He said they transfer a lot of vibration into the valve train and have had more issues with valvetrain breakage with people running gear drives than anything else. And he talked me out of a fluidamper as well. He said unless you are turning twice the rated rpm's, they do more harm than good because of the added weight in the end of the crank and a quality factory damper will actually keep more vibration down than a fluidamper in the factory rpm range. It makes sense, and I trust him completely. The new engine will be getting a girdle though, among a host of other things.
 
I am only suggesting an odd known case of later failures from hydrolock not that you experienced the same day failure. I merely suggest this and fatigue as other possible causes in looking at and over the edge of the limits of things. I am generally the first to say "new parts are not always good parts." Glad the block can be saved!

@6.5L you wrote the book on doing something like the BD spool valve because "it couldn't be done." First off: Your money and your engine build so we are along for the ride no matter what. :) I wouldn't bother putting a gear set on a 350 or 454, but, I get sick of low mile stretched out chains on the 6.2/6.5 esp with how deeply buried they are in the front to get to. I dread the job Patch needs from both the IP and chain slop making it a fogger on start up in our warm weather. Patch doesn't have that many hard miles on the chain! Gear set in stock ready to go on the moment the 1992 project gets out of the garage.

The moment we put the injection pump on top of the timing set all experience with chains go out the window.

Gas engine experience isn't really relevant to a diesel engine especially this diesel engine. The Chain/Gear to IP drive is a holdover from the same tooling as gas engines Olds diesel hand grenade that generally didn't last long enough to concern GM about chain life. (Design Emissions life 50K and vehicle life was 100K back then. Regardless the Olds Diesel made Lemon laws happen. ) Most running gear drives are Hot Rod or Race engines pushing the ragged edge of destruction vs. the casual 4 wheels and a box that keeps a boring chain if the OEM can't put a life limited timing belt on it. IMO the Rat Rod/Race engines will have more trouble than most because of what they are and being used as such. I suggest "heavy duty gear drive timing diesel engine experience aka Cummins" would be more relevant. They go 1/2 to 1 million miles on the timing gears. Gear rattle at idle from an out of sync CP3 is the only downside. (Factory procedure now on 6.7's to correct this NVH CP3 sync.) I have to break arms and knock heads together to overcome the "we have always done it this way" combined with awesome fear of something new like gapless rings.

6.2/6.5 diesels eat timing chains for breakfast because the high sudden load from the injection event stretches it out. The entire valve train is an irrelevant load vs. the injection pump's peak load, that happens after the injectors pop. The peak load from the IP is what stretches the chain out. The IP that is gear driven off the camshaft - likely only because a cheaper chain couldn't do it. The chains are sloppy garbage at 30K miles with GM just making the limit specs to .8", that's nearly an inch of slop, just to get by. That 0.8" is from chain stretch not wear. My 1992 project thread should illustrate what a sloppy timing set does to the valves: it hammers the exhaust valves so bad into submission the tips start fatigue flaking. (Timing set pics. Valve stem flaking.) Even the highest quality Cloyes chains are stretched into submission as I found during unexpected low mile tear downs.

If you ever get ahold of a timing scope and watch the timing bounce all over the place with a worn/sloppy chain on a gas engine and then figure the 6.2/6.5 chain is sloppy at 30K miles the extra vibration theory just sinks from being slapped around from chain slop.

The final nail in the coffin for your engine builder's "opinion" must be a lack of experience with a similar "Forgotten Diesel" to ours found in Ford aka the 7.3 IDI's all gear timing set that lack the stretched chain trouble and need to retime the IP often. This is why the Ford DB2 IP's turn backwards from ours:

7_3PSD.jpg

/Rant
 
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I agree on the above. Love your builds, and can't hold anything against a decision of aftermarket components, but since I have 2 pennys in my pocket:

Gear drive is on every diesel worth a darn. They can be hell on gas engines, and above 7,000 rpm get ugly quick. Db2 on fords outlast them on gm because of it. Haven't seen too many valve chatter problems, infact 6.2/6.5s loose more pushrods and lifters than 6.9/7.3 did in the fleets. The double roller chain on ours is as high quality as most high perf gas engines get, and we destroy them. Guess how long a single would last- haha.

The weight of the FD is high, but they hold a great record. The quality of the factory balancer is crap. My last AC Delco and GEP balancers let loose in less than 100,000- and those are supposed to be the best out there. These were not hopped up engines btw, and never got to 4,000 rpm. Infact, how solid is yours on the lower end killer? Grab that sucker and give a few yanks, might find the rod killing issue.
 
Meaningless at this point, block got flux'd. It's toast. Looks like I am heading back to the 599. Who knows. Got a lot of decisions to make
 
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