I'm just curious how many of you have actually had or been witness to a cummins blowing up, or seizing up or whatever. And if you did what was the cause. Thanks

 

I have seen two, one 350 big cam and a 1998 5.9. The 350 big cam was in an old dump truck a contractor used that I was working for. It died from what I would gather a bad oil pump, sent pieces into the oil pan when it went, and cracked the block. The 5.9 died from overrevving, I don't know how it happened but the owner told me he was climbing a hill loaded and the trans broke the input shaft. Same scenario, pieces laying in the pan, cracked block, and a cracked crankshaft. Oh, i did see a 5 ton military truck blow once with the 280 in it. It was running down the road full throttle, cracked the block in the center from oil pan to head on the pass side. For the most part these engines are strong and forgiving as long as they operate within reason.

 

I have. Cause was mixed between owner ignorance and previous owner stupidity. Two months after I bought the truck, I had checked all fluids, changed the oil, air filter, tranny fluid, rearend gear oil. Checked the brakes, even changed the brake fluid. Well, in my attempt to go over the truck as best I could, I LOOKED into the radiator. Didn't test it to see how much antifreeze was actually in it. well being the sentimental idiot that I am, I had my GF's picture on the dash,,,covering up the temp guage. Temp dropped below freezing for two days, and off I went in my new truck that I loved so much, drove for about 2 hours. Never so much as thought anything was wrong, till driving down a straight stretch of road I smelled burning oil,,,turned down the radio and heard VALVES TICKING. OVER THE SOUND OF THE DIESEL CLATTER! So I immediately let off the fuel,,,and instead of doing the smart thing and pulling the kill switch immediately, I saw a nice gravel turnoff and gave it just a tiny bit of pedal to keep enough speed to coast to it. Well just as I did that, the head gasket let go majorly, and bang, big flame out the stack. Sounded like a 747 backfiring,,(whatever that sounds like lol) well it quit running,,,and not really sure what to expect I poped the hood and saw oil gushing out behind the motor between the head and block along with a nice geiser of steam. Thought maybe I just got lucky and blew the head gasket,,,took the head off 2 days later and WAM the back piston was toast. The other 5 looked alright but they had little dimples in them. Once I got them out, every one had melted skirts and cracks. The #6 cyl wall had DEEP grooves in the bottom ,,,although the top looked fine remarkably. All the damage came from the skirt cracking and the grooves ended up below the rings. I bought new pistons, honed the cylinders, had the head decked, boiled and magnifluxed, rods magnifluxed, new rod and main bearings, put her all back together. Have very good compression in all cylinders, over 60psi of oil pressure when warmed up. Surprised I didn't ruin the motor. I'll get a new block eventually , those grooves still scare me sometimes, I'd rather have it pristine, they aren't hurting anything that I can tell, but I still know they're there. I've heard boring the motors isn't good if you've upgraded, and I'd probably have to go at least .050 over to get rid of the grooves. Don't even know if you can go that big ? Wish they had sleeves like the C series motors!

 

Watched a 94 3500 tow truck grind itself to death. Truck was brand new.

Driver pulled up to an accident scene. Got out of the truck with it running. Problem was he left it in neutral and with the park brake off. Just as the door clicked shut, off she went rolling down the hill. Went over an embankment, landed upside down in a drainage ditch. Ditch was just the right size that you couldn't get to the doors to shut it down.

Everyone was a little suprised it ran as long as it did. Fuel didn't seem to be a problem, but lubrication was. It made some god awful noises and then died. Found out later from the dealer that it siezed solid from lack of oil.

Sad sad day it was.

 

I really don't want to talk about it.... Lets just say my motor mounts have wing nuts on them....

 

I really don't want to talk about it.... Lets just say my motor mounts have wing nuts on them....

I know How you Feel . There has been two times now in the past year that we have ate a piston. And no they don't taste good!!!! But we do haul a lot and now have the problems worked out, so all is good for now!!!

 

how many miles you got on the refresh? I've got a block in the garage that has some grooves in the #6 hole. they don't sound as bad as the ones in your block, but I don't think they're gonna hone out all the way.

Forrest

 

I've had two towed in, not mine, with melted pistons resulting from power modifications with no pyro.

 

wish I had some pictures of a Signature ISX I had converted for experimental use of Natural gas. had a injector go bad and it blew the front half of the head and the front upper part of the block clear off the engine. Got a M11 out of a car hauler sitting in the shop right now that split the block clear in half right at number 4 cylinder. only the head and pan kept it together. what a pain getting that one out was......

 

Number one engine was #53, cracked at 60k
Number two engine was Cummins recon, warranty, a new thermostat seized #1 at 241k
Was overhauled, did not know that the thermostat was bad, left it in 950 miles #1 seized
Number three engine had the #53 ground off, lost a head gasket at 4000 miles.
Number three engine cracked at 6000 miles.
Number four engine is the ISB275 commercial engine, fantastic engine.
Lost the head gasket due to leakage at the front corner. Forget the miles, it now has about 65k on it. It does have a bad oil leak, can't seem to find it, think it is the pan rail cracked from so many installations. Leaks a quart a thousand right now. Real messy. Warm weather will bring a fix.

 

53 ground off??? well thats just dirty pool.....

Thanks for the idea....lol. JUST KIDDING.

 

HID, was it you that said they got a generator enigne, not intended for on road use?? Read that somewhere here i think...

 

That would have been the #53 with the numbers removed. It was sold as a new commercial long block.

 

i saw a 469 cummins get a piston gaulded up and seperate from the conecting rod and sling the rod through the side of the block on both sides, major havoc, the crank was in perfect condition still though

 

Saw an old 440 gasser in a pulling truck that broke a rod midway between thepiston and the crank, rod swung around and busted a 3" chunk out of the cam shaft. Truck was still running on the front four but didn't want to pull the sled too far.