Anyone tore down a rough one?

[spencerdiesel]

An engine that's seen high exhaust temps for most of its life:

Sled puller, street toy, heavy tow rig. Anything that's seen >1250 for uncomfortable lengths of time.

Saw a 426 hp non IC VE bellow a steady flame out of the tail pipe for over 30 seconds......guessing it was warm

[ellis93]

I've seen shrunken piston and cracked ones on 7.3powerstrokes. Seen a few gualded piston skirts on one 24v cummins and a 12v with chunks of piston in the pan (it came in with a miss,no major noises). I've often wanted to see how a cummins holds up under high temps......I just don't want to have mine be the test subject lol

[spencerdiesel]

I wish Cummins would test one to failure, then publish the sustained temp at which things started going south.

Were these engines modded?

[ellis93]

I wish Cummins would test one to failure, then publish the sustained temp at which things started going south.

Were these engines modded?

The two powerstrokes were chipped/programmed with no gauges. The cummins where just worn out/abused. One was a farm truck,the other was in a snapon tool truck(lots of idle,running around)

[DMan1198]

Took one apart that ate a valve. Took a 40 thou overbore to clean up the scoring, and the piston was destroyed (it actually had a piece of valve stuck in it) did a 6.7 that'd been dusted. The cylinders weren't actually too bad, but the rings were not in great shape. The broken cam ve engine I got a while back has cylinder walls that look recently redone. I'm actually a little stumped as to why the cam broke.

I've redone plenty of Waukesha, and cat engines that've been really bad. Worst one was a 3512 cat that dropped 2 valves, and destroyed the top of the piston so bad the top ring came off. Also did a 3408 cat that broke all but 2 valvesprings (so 30 valvesprings) broke 1 bad enough it it popped the retainer, and keepers off (and we never did find one of the keepers. Probably what all the metal shavings were)

[79Powerwagon]

This was a 3408 heui in a D9R.

Turbo failed and engine ran away. Flames out the stack. They attempted to shut it down with a fire extinguisher. It kept running and eventually died.

It drove into the shop after a new turbo was put on.

3 melted pistons and a bent rod. Wasn't easy pulling the piston /rod out of the liner.

[spencerdiesel]

Fascinating info, any idea how long the 3408 ran away for?

[79Powerwagon]

Don't remember how long it ran away for. Til it starved for oil I suppose.

[spencerdiesel]

Did older Cats have tattletales? I've heard of plastic inserts that melt at a certain temp for warranty purposes

[79Powerwagon]

I've seen small stickers with temp ranges on them. Most are usually toasted on equipment

[spencerdiesel]

Who has towed heavy with a lot of timing?