Run Away Engine

[FarmerJones]

Recently I went to start my 2002 New Holland TC40D Tractor. After the glow plug light went out and upon turning the key, the engine immediately went to full RPM, pegging the tach. I turned the key off and removed the key, with no effect. Checked to see that the throttle was completely in the low position, it was. Lifted the bucket, lowered the brush guard, opened the hood and looked at my motor in amazement as the barn filled with black smoke. Turned off the fuel supply, and proceeded to close off the air intake. This caused the motor to slow some and with continued effort killed the motor. The dealer repeated the process a few days later to the same results, engine ran-away. Intially the dealer was going to fix the motor, after some discussions, they completely replaced the motor with a new one. Anyone else out there had this problem? Any thing else on the tractor that I should be concerned about?

 

[SnowRidge]

Sounds like it might have been running on its own lube oil, if shutting the fuel supply off had no effect.

The dealer and NH did right by you by replacing the engine.

We had a lot of diesel powered generators when I was in the service. A runaway diesel was not to be taken lightly. The drill was to first shut off the fuel, then choke off the air if you can. If that didn't work immediately, run like ****.

SnowRidge

 

[DavidJ]

I've seen a couple of them run away when someone put gasoline in them instead of diesel. I'm sure that wasn't your problem because the dealer would have surely said something about it.

Glad to hear that they treated you right by replacing the engine.

 

[kensfarm]

I didn't have your problem w/ the runaway.. but I had my engine replaced due to damage from overheating back in 2000.. I wonder how many TBN'rs are in this "engine replacement" club. Glad they did the right thing.. don't forget to change the oil for your new engine after 50 hours has elapsed.

 

[Soundguy]

In 2000 I bought my NH 1920 from our local dealership. It was used, and was a 1997 model, and had originally been sold from that dealership. The guy bought it, and by 2000 something had gone wrong in the engine, and they ended up getting him another tractor ( was some price difference, as he traded upin size too )... anyway, I got the tractor wit 700 something hours on it, 4 hours on the rebuilt engine.. has been good since... Perhaps a few years ago they had a bad rash of problems at the plant?

As a side note, our deisel mechanic used to work for Ringpower, and their standard procedure for working on diesel engines after rebuild was to have a choke plate ready to throw on the air intake for just that reason. He said he had seen some older engines suck thier pcv seals in for air, and start pumping the crankcase oil for fuel.. had to load the engine down to kill them... that would be one of those tense moments i guess....

Soundguy

 

[FarmerJones]

Suspected the rack stuck in the fuel pump, allowing it to go to a full fuel output status.

 

[SnowRidge]

<font color="green">( Suspected the rack stuck in the fuel pump, allowing it to go to a full fuel output status. )</font>

Oh, I thought you had shut off the fuel, presumably with a valve in the line. I'm not familiar with NHs.

Did the dealer suggest a stuck rack?

SnowRidge

 

[FarmerJones]

A Cat Mechanic suggested the rack problem. I had shut the fuel supply off, but it continued to run on the fuel that was in the filter bowl.

 

[barogers]

I had the same thing happen to me about 15 years ago while I was in the Marines. I was driving a 5 ton up to Camp Lejune and while coming into a town the thing just wanted to keep full throttle /forums/images/graemlins/shocked.gif. Needless to say, but I will anyway my excitement level increased to about max too /forums/images/graemlins/shocked.gif. To top it off, I was carrying a full load of live ordinance, ammo, H.E. ammo, grenades, mortars, etc. I had to take it out of gear (it was the new 5-speed automatic) to stop and to go, put it and brace for a serious slam. I finally got it pulled off in a clear area off the road outside of a small town, called it in and had to stand armed-guard for about 12 hours until a wrecker was sent from Camp Lejune. I am sure I looked kind of strange standing there with an M16 and Shotgun /forums/images/graemlins/grin.gif. But one thing was for sure nobody would've got that stuff without a serious fire-fight. According to the mechanic a valve-pin in the fuel injector stuck open (actually broke) and caused the problem. Not sure if that CAT250 is built the same as your CUT engine, but would think it would be similar in most respects.

 

[5030]

Being around diesels of all sizes for the last 35 yeras, I have seen some interesitng things happen. I've seen mechanically injected Cat's run backward, sucking air through the exhaust pipes and belching black smoke through the air cleaners.

I've seen 2 stroke Detroits run away (they had a choke plate built in the air intake above the blower for just that reason).

But the best one that I know about is a friend of mine that had a 3406 B mechainically injected 425 cat in a Western Star. The 3406B is air to air, meaning that the charge air is run through an intercooler after leaving the turbo and before entering the intake manifold. Anyway, the oil seal on the cool side of the turbo started leaking. That started putting a small amount of oil in the intercooler body. After a few days, when the intercooler filled up with oil to the top and he was driving down the road, the engine got a suck of crancase oil, directly in the air intake. Needless to say, it took off. As the rpm's increased it started sucking more oil. Les (the owner), pushed in the clutch and keyed the engine. (no luck). Let the clutch back out and stood on the brakes (took out the driveshaft and grenaded the clutch) Jumped out of the truck and watched as parts came through the hood!! Upon teardown, the engine had broken the Jacobs brake arches (no small feat) and the No. 1 piston went through the head. There was also a hole in the block just below the exhaust manifold on number 6. The cam was wiped, transmission gone and the driveshaft looked like a pretzel. The truck had a mechainical tach in it and it was pegged at 3500 rpm and stuck there. Cats are terminal at anything above 2500 unless they are V8's.

The underlying theme here is if it runs away, get away. The engine becomes an iron grenade. Besides, that's what you have insurance for.