doesn't turn off

[millican]

I pulled in at home last night and turned the key off and took it out. The only odd thing is that the engine kept running. If I push the accelerator, it responds just as it would on the road. The instruments are dead, but it does seem to run normally. I stopped it by putting it in 4th, holding the brake, and letting off the clutch. I hate to do that though.

 

When the key is turned off, what actually changes that shuts the engine off on a diesel? Most of my tools are in Arkansas (and I'm not), but I do have a multimeter.

[datsunaholic]

There's a solenoid for shutting off the fuel at the injection pump, it's probably stuck.  Might have something stuck in the needle seat.

[millican]

I think that's it! There is a connecting rod about 6 inches long that goes to the actuator. It had come off recently. I assume it was recent because it was nice and shiny; unlike everything else down there. I should go to the hardware store and get the right size retaining clip to hold it in place. Thanks!

So also, the engine is shut off by cutting off the fuel supply, whereas in a gasoline engine, you can cut off the spark?

[datsunaholic]

Cutting the fuel supply is the ONLY (normal) way to shut off a diesel.  There's no external ignition (fuel, air, + compression, that's it).  I've run diesel engines with no electrical connections at all once started.

 

Shutting a diesel down once it's found itself an "alternative fuel supply" (like a leaking oil seal in the turbocharger) gets REALLY fun.

[millican]

I've seen the runaway diesels you mentioned; most recently a semi near the top of a long gradual climb. Holy Smokes!

[wayno]

So your injection pump control rod fell off the injection pump?

There is a cotter key, washer, and spring, these are what you need, although a cotter key alone will likely work.