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Runaway Detroit diesel

Yeah, Like what's the big deal ? Isn't that what a 2 stoke detroit is supposed to run like ?
Back when I drove truck I spent some time behind a 6v71 and an 8v71.
Wind em up and keep em screaming. Nothing like a 2 stroke Detroit diesel when it sings its song. Greg.
 
Just FWIW, a Detroit that has been sitting for a very long time is much more likely to run away because the shaft oil seals in the blower have gotten hard and either deteriorated or disintegrated with time. This allows straight crankcase oil to get into the cylinders and away she goes. Many have an emergency cut off which is nothing more than a choke / strangler that tries to cut off the incoming air. They don't always get the job done.

The best way and least damaging way to kill a runaway Detroit is to cut a large CO2 fire extinguisher loose into the air intake. That will kill em dead quickly without hurting them.

And, yes, there is something about an old 2-cycle Detroit right up "against the governor" "singing for it's supper"
that sounds so good! ! Especially an old 6-71 or 12V-71! ! ! ! ! ! ! The 92-series (last of the 2-strokes IIRC) didn't have quite the same sound. Yes, I love Detroits! ! (The only good engine GM ever made! ! ! !)

Frank
 
Detroits are not the only ones that do/did this. Some of the old Cummins engines from the late 50s/early 60s were so bad to do it they were called "Cum-aparts" by the truck drivers (including dad) who drove them, because once they ran away, that is it... new engine time.

--Hawk
 
I was not there when it happened. But I got to see the aftermath from a run away V12 cylinder D398 Cat marine engine in a tug boat. It had just been install in the boat, had been running. They had puller the governor off for some reason, and didn't get it re connected to the fuel rack right. They couldn't get it shut down because it was drawing fresh air in from the ducts to the intake.
It threw a rod out through the side of the block and dented a 5/16" thick steel hull.:hitsthefan:
 
On a slightly different note I have witnessed several Gardner diesels where the driver has stalled the engine and on the rock back with transmission wind up they have started up again backwards. Drawing air through the exhaust and exhaust smoke coming through the air intake system. Most drivers flapped around thinking they were running away but they just idle away although not quite as happily as the correct rotation. I have been told that the Perkins R6 was prone to this also but i have not witnessed one doing it.
Steve
 








 
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