OK, I just scared the edit out of myself. I was hitting it hard from a red light going thru the gears, when something happened and the RPMs just took off. I guess it was diesel run-on, because I tried shutting the ignition off, but I just lost steering pressure...engine was still running wide open. It all happened quickly, I'm not exactly sure everything I did, but I don't think I turned the ignition back to ON because I never got steering back. I was able to get it to the side of the road, in a ditch, where I was able to stall it out. It ran wide open for a 2-3 minutes...I thought it was gonna blow up.

Checked the throttle linkage, and everthing looked good, but I'm no expert. The linkage and cable seemed to be working, pedal felt fine. This is a new-to-me truck. PO said it has a precision diesel IP with some upgrades, a #11 fuel plate (I moved it from all the way back to halfway) and 3GSK.

I couldnt get it to refire after this. It didnt smell like any fuel was coming thru the exhaust when we cranked it. We towed it back home, where I parked it, grabbed a beer, and am gonna forget about it til tommorow.

So, what else should I check besides the throttle linkage? I have a feeling I'll be using alternate transportation on Monday.

 

It had to get fuel from somewhere if you switched off...is the turbo leaking oil into the intake?

 

I don't know..it wasnt smoking like it was sucking oil. Remember, this is the 12V mechanical lift pump, so turning the key off doesnt shut it off. There's a fuel cutoff solenoid, but I 'm not sure how it works (or if mines not working).

 

You lost steering because you locked the steering wheel in position while turning off the ignition key? Otherwise, with the engine running (even -on), you should still have had steering-assist pressure.

 

I think you may be right. I was trying to shut it down while slowing down so I could pop the clutch and try to stall it. It was a little unnerving listening to the motor tach out, then when the steering stopped...

Anyways, shouldnt the fuel shutoff solenoid prevent a runaway engine? And what might cause the throttle to take off?

 

The fuel shutoff solenoid won't have much of an effect on a runaway diesel, since the extra "fuel" that causes runaway is usually from something other than the fuel delivery system.

I don't think you experienced runaway - just something stuck when you hammered it away from the red light.

Don't worry about running your Cummins at rated speed - they're designed to do that (hence their medium-duty classification).

Try to repeat the problem in a safer environment - like in the driveway.
Have you checked your oil level?

 

My old 94 12v had this problem. A temporary fix is a can of wd40. Start spraying and work it back and forth. You other poblem could be the return spring. About 2 or 3 years ago Dodge came out with a recall kit for the linkage. The lower return spring has plastic on the spring ends and all it does it trap moisture. So the ends rot out. More than likely you lost that spring and have been wearing out the circular spring. But thats a long shot. What really needs to be done is to pop off those linkage bars and check to see which one is sticking. But while you have them all off. Soak them all in some motor oil. But if you are going to have it fixed at a shop. I would bring it to a dealer since all recalls are gaurenteed for life of truck. So it maybe a free fix. or it may never had recall done

 

Engine oil level looks good. I didnt try to fire it up yesterday. It wasnt firing Saturday night after the shutdown, and when cranking, it didnt seem like any fuel was coming out the exhaust. Tank is 3/4 full

 

No fuel out of the exhaust is usually a good thing, unless it's Bombs away!

Like BigDave said, make sure that linkage is working properly - first it's running at rated speed after lifting, then it won't fire off in the driveway... the signal from your right foot is obviously not making it's way to the injection pump correctly.

 

Is this second spring a linear spring? I don't think my truck has one, just the torsional spring under the throttle linkage pivot . Any one got pics of how the throttle linkage should look....manual transmission, not auto tranny kickdown brackets please. There is an arm off the linkage that looks like a good place for a linear return spring, I'm not sure where the other end would go.

Would the throttle linkage recalls still be honored since I have an aftermarket injection pump? Maybe a dumb question, but I don't know the answer

 

The right foot is moving the linkage on the IP, but I have no clue what goes on inside the IP.

Rated speed?...when I lifted, the RPMs when way past any governor settings, I think it maxed out the tach. PO said he put a 3GSK and #11 fuel plate, in additon to the precision diesel IP.

It seems like no fuel is being delivered; it didnt even stumble when cranked. I would have epected to crank some fuel thru the engine and out the tailpipe. Could my fuel shutoff solenoid be sticking in the closed position now...and it was stuck in the open position Sat. night?

 

The fuel shutoff solenoid wouldn't cause the engine to rpm like that, but just pull it back manually to try and start it (should be able to watch it move itself when cranking).

You saw the tach needle go past 3500 rpm?

Sure sounds like something broke inside the IP!

 

yeah, I guess you're right about the shutoff sol...it had to be internal to the IP. The tach needle was buried, I can't say I remember exactly where, because I was trying to slow the truck down with the steering locked 30degrees to the right

 

How did you finally get it shut down? Have to stick your coat into the intake?

 

sounds like a WILD ride!