The reason why this Detroit diesel was getting out of control and ran at runaway speed, is that one of the injectors was stuck. On a couple of photos, you can see me pointing my finger at the N45 injector that is stuck.
If you are visiting this page from your favorite search engine looking for stuck detroit diesel injector, here's how I fixed it. I took it out of the engine, put in a can of carb cleaner for a couple of hours, and patiently loosened the arm with a tiny brass hammer.
Click here to see the engine running.