Runaway Detroit Diesel

Used to drive an older Freightliner cabover with the Detroit V8 2 stroke....had to speedshift the damn thing, the running joke was "drive it like you slammed your dick in the door"

A few old potato haulers in the area still have the Detroit V8...
 
Truck/trailer I drove for the implement dealer had a detuned 671 in it. A gutless 219 Hp. Did okay empty, but put a tractor on the trailer. No one home.
The 671 will always be gutless. I drove one for years with 10 speed road Ranger
We has a 3208 cat with 5 & 4 . I was of a couple people that could drive it.

I liked the Cummins Big Cam IV
Not a fan of cats. Drives like but mechanically they unnecessarily complicated.

I never drove a Detroit silver 8V92 but the twin turbo was suppose to move.
We had one at school on a test stand.
 
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These guys are showcasing that they know nothing about these engines. They are governed to 2,800 rpm.

The only thing that "fails" when running one without coolant is the piston skirt will spot weld to the cylinder wall.
I work on EMD locomotives. 16 cylinders 2 strokes . Same basic engine .

About 760 ci. per cylinder. 4000 hp turns the main and auxiliary generators.
The mains are about the size of a 3lb. Coffee can. When they fail and they do fail it is catastrophic.
 
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Different engine. GE 7fdl
16 cyl. 4 stroke.
The picture is from the crank upward. One rod sheared in half. They are about the size of a small arm. Both rods connect to a trunk on one journal. You can see part of the crank web , cam section (8) per side and what's left of the liner and piston.
 
The other thing is when a diesel engine runs away , usually it would run on oil supply from a failed turbo. At the point of run away there is nothing to govern rpm because it is no longer running on fuel.
You actually "get" it, and this is exactly what the video makers did not touch upon.

Unmetered/uncontrolled fuel will result in excessive and uncontrollable engine rpm. Since a diesel has no way to meter air (as you know, it is an open intake with no throttle valve) it will never 'run out' of air and the only way to shut it down is to block off the air intake.

I have watched my Pop shut down a Detroit runaway with a piece of plywood and he just slapped it over the air intake.

I never liked Cummins-Apart or Clatterpillar. I preferred the simplicity of the Detroit.

We worked on quite a few Deutz Air Cooled Diesels that were used in industrial applications. When I was a kid growing up, we had a lot of wind machines in the citrus groves around our ranch and Pop and I worked on all of them.

Many used a Ford 317 CID (and some 341 CID and 368 CID Lincoln V8's) which Ford marketed as an Industrial Engine, but some wind machines used the 331 CID Chrysler Industrial Hemi.
 
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The old 318 Detroits were the gutless wonders, but the big ones they put in the truck’s in 79- up would pull mountains like no problem.. better than the Cummins 400 big cams

Even "tweaked," the 425 HP Clatterpillars and the 400 Pig Cams couldn't stay with our 'tweaked' V8 and V-12 Detroit's. When I was driving (part time for a friend's dad) for B&G Trucking in Santa Fe Springs back in the 1980's, I have pulled the Grapevine on I-5 with a 352 Peterbilt Pacemaker COE at 76,000 GVW with the 12V-71TT doing 65 mph in the middle lane at around 2,000 rpm.

The 12V71TT was rated from the factory at 1,400 lbs/ft of Torque at 1,600 rpm and we had increased boost and altered the rack adjustment, so I am not sure just how much steam we were putting out.

Now, the 12V-92TT was another thing altogether. The '9G90' variant, which we only saw in certain long wheelbase logging trucks, made a whopping 2,040 lbs/ft @ 2100 rpm....

12v-92TT.jpg
 
The 79 Pete CO I drove had a big Detroit, don’t remember the engine number, but I could pull Needles grade west bound at 50 mph with a 13 speed road ranger, and never have to go past 10’th gear.
And I would have guys telling me I must be empty, but we would be hummping the full 80,000 pounds
Tractor an trailer
 
Even "tweaked," the 425 HP Clatterpillars and the 400 Pig Cams couldn't stay with our 'tweaked' V8 and V-12 Detroit's. When I was driving (part time for a friend's dad) for B&G Trucking in Santa Fe Springs back in the 1980's, I have pulled the Grapevine on I-5 with a 352 Peterbilt Pacemaker COE at 76,000 GVW with the 12V-71TT doing 65 mph in the middle lane at around 2,000 rpm.

The 12V71TT was rated from the factory at 1,400 lbs/ft of Torque at 1,600 rpm and we had increased boost and altered the rack adjustment, so I am not sure just how much steam we were putting out.

Now, the 12V-92TT was another thing altogether. The '9G90' variant, which we only saw in certain long wheelbase logging trucks, made a whopping 2,040 lbs/ft @ 2100 rpm....

View attachment 87331
2 6V92's , cranks and blocks bolted together. One bad mother. The Screamon Demons are fun machines. 2 strokes going the way of the Dinosaur. Becoming extinct by now.
 
WOW, you guys sure know all manner of engines, part numbers, specs etc,

My experience with Detroit and Cummins diesels amounts to seeing exhibition Truck Pulling Detroits pull a full pull and then some on engines with over 1 million miles, and Over the road Passenger Dodge Dually trucks with 500-600K miles of hauling trailers full of cars and trucks up ad down the road from Md to FLorida.

Sumn Similar to this.

 
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