We had a Case farm tractor do this. Mechanic was on a service call. Ran away on him while he was diagnosing an issue the tractor was having. Don’t remember how he killed it…. But he did. Enter me. Drove our truck and trailer to pick it up. Winching it on the trailer unfortunately it wasn’t rolling straight. Tried a couple ways to get front wheels straightened out and couldn’t. So…… made sure stop cable was out. Fuel shut off at tank. Was going to use starter to turn engine over a couple times for hyd pressure to steering cylinders….. and the thing started. So I chucked it into 4th gear and slowly let clutch out and that killed it. I did have the presence of mind to turn steering wheel while it was running.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.
It was determined the run away was caused by the rack in the inline Bosch injection pump that had broken.
Don’t remember the engine having a turbo. Want to say it didn’t. Lots of hypothesis why it did it, but no consensus. Several really smart techs ultimately shrugged shoulders and said…. “Don’t know.” I can say. It was really exiting for a few moments. Pretty sure I didn’t want anyone taking my blood pressure immediately after.



