Starting a 671 Detroit after sitting for 35 years

The 671 had not been started in nearly 2 years and had never run away on me in the past.

I got her puffing on starter fluid then once she seemed like she could run on her own I gave her some fuel with the foot throttle and then she immediately went full blown wide open.
It scared the holy crap out of me.

Its like when that happened time came to a stand still and my brain did not even function and was only in reaction mode.

Very weird

Right away I had a steel plate just in-case sitting on standby if it ever decided to run away. Once the plate was over the intake she only came down a little bit, so I took my foot and stood on the plate over the intake while reaching inside the cab pulling as hard as I could on the fuel cut off valve.
I did notice a difference when pulling on the fuel cutoff. Overall it took a few minutes for her to wind down and die, but seemed like a lifetime.

Once the smoke cleared I thought for sure the fire department or the police were going to show up.

Was insanely loud.

The sound of a straight piped 671 running away was immense.

I cannot emphasize enough the level of sound that motor puts off when straight piped and at full throttle.
 
It probably would have ran away on the ether if it was running on oil. I'd say something with the pump.
 
Two stroke diesels are fun and you can see and understand the fuel system I have seen several detroits run after being stuck one was even under water I have faith you can find all the info u need on the net. I am new to this forum but I've been a diesel tech for 12yrs and all the two strokes ive seen or worked on run 15w40, in the cold i would not run a straight 30, oils have changed a lot since detroits were built. Im not trying to start an argument as usually i only run what the manufacturer recommends but what I have seen of older engines is they dont mind better oil than what was around in the sixties between my brother and I we own 3 old diesel 2 case and one 4-53 they all call for 30w but we run 15w40 all year same with the 2 gas engines they get 10w30 now. the owners manual for old equipment often tells you to run thinner oils in winter or some even say thin the oil with kerosene (dont). I think if they had multi weight oil back then they would have used it. Just my 2 cents but not saying its right lots of people say only straight 30 for detroits. It would probably last forever as long as it has oil of any kind in it. They are rugged engines i hope to hear you get it running.
 
This came to mind instantly. These guys were ready for it too... so they thought.

[ame="http://www.youtube.com/watch?v=8M1o2rpO_JY"]http://www.youtube.com/watch?v=8M1o2rpO_JY[/ame]
 
That truck is flat neat!! Only experience I have with detroits is the 3-71 in our 990 oliver. Basically Im subbing to see your progress lol.
 
Subbing, always love to see old iron return out of the woods and fencerows! Good luck sir!
 
Honestly I haven't done anything with it. I wanted to get it running for a few reasons. One to move it around, have fun with on the farm [maybe tag it historical and take it to pulls or shows] and for my 86 year old Grandpa to see a truck he drove for so many miles alive again for the next few generations to see. Unfortunately, GMA passed in Oct and GPA passed in Jan. I'm not sure what will become of it now, priorities on the farm have shifted, but I hope to do something with it eventually.
 
Man sorry for your loss, hope things work out and you can get that old truck going again. It'll be worth it speaking from experience.
 
on some models, the drive between the blower and governor can fail. The result is that the blower and engine work just fine, however the governor"sees" 0 rpm, just as if it was stopped. As someone else stated, when stopped the governor's default position is FULL FUEL. This actually as much as the pump can deliver, which can be considerably more than the rated horsepower fuel setting. Had a coworker who had this happen years ago, he said it suddenly started pulling way harder than ever before
 
If the blower shaft is broken. The engine will not start. It will turn over fine. But there is zero chance that a two stroke diesel will start If the blower shaft is broken.

If it breaks while running it will continue to run. But once shut off it won't restart.

2 stroke Pistons do not create any vacuum in the cylinders to draw air in for combustion. You can thank intake ports in the liners for that. Which is why Detroit Diesel calls them scavenge pumps. Not blowers. Which is also why two stroke Detroits that are not turbocharged are considered naturally aspirated even with a blower.
 
We also used dual grade oils in Detroits for years and years through the winter in forestry equipment and never seen an issue from it. One of the best days of my life was jumping in a inline six skidder and never having to put another day in on those God forsaken Detroits.
 
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