Engine trouble

[John_Mc]

I'm having trouble figuring this one out:

2001 NH TC33D with about 1800 hours on it

I had not run the tractor in 2 or 3 weeks. Fired it up ran it for a few minutes to take the tire chains off, then shut it down. Started it up a couple of minutes later and it seemed to run normally for a minute or two, then sputtered, started sounding as though it was not firing on all cylinders, then died. Tried to restart, ran rough for 20 seconds or so and died again.

I dropped the fuel sediment bowl and pulled out the fuel filter. It had a bit of water in the bottom of the bowl, and some rust on the lower edge of the filter. Drained a pint or two of fuel. First pint looked cloudy and had a bit of water in the bottom, second pint still cloudy, but no water pooled in the bottom. Drained another quart out which looked good. Put in a new fuel filter, bled the fuel lines per the owner's manual. Fired it back up and it ran normally while I swapped the bucket out for the grapple. Drove a couple hundred yards back to the garage and it started losing power, then ran rough and died again. Dropped the sediment bowl again - fuel in it looked good, no water. Drained more fuel which looked good. Bled the fuel lines again. It fired right up and ran... for about 15 seconds, then sputtered, ran rough and died.

On the theory that the fuel was bad, I drained all fuel from the tractor tank and sediment bowl, poured in a gallon from my fuel can, bled the lines. It fired right up, ran well for 30 seconds or so, then sputtered along on two cylinders for a bit and died. It's possible that can of fuel was bad. Tractor was running OK when I last used it. I poured a gallon or two from this can in the tractor the last time I used it. I dumped the rest of the fuel in the can and bought some fresh. Will try that if I have time tomorrow.

Still using the same new filter I put in after that first draining of fuel. It looks fine. The sediment bowl never looks starved for fuel. It fills right up quickly any time I turn the fuel back on after draining

Any thoughts on what's going on?

 

[dodge man]

I’d guess like you are bad fuel. Any idea how old?

 

[John_Mc]

I’d guess like you are bad fuel. Any idea how old?

The gallon or so I added after fully draining the system was two or 3 weeks old. I'm wondering if that 5 gallon can was bad when I bought it. The problems started with what I THINK was the first run after adding a gallon or two from this can shortly after I bought it.

 

[thclimer]

Sure seems like its fuel related as well to me.

 

[John_Mc]

That's where I'm leaning, but the fact that it won't run after completely draining and then adding 2-3 week old fuel threw me. I supposes it's possible that "new" fuel was bad.

 

[thclimer]

When it shuts off is there still fuel in the fuel filter bowl?

 

[dodge man]

When you say the five gallon can was bad what does that mean? Are you storing the fuel outside where water can get in? If you store it inside the fuel was probably ok unless it was bad where you bought it.

 

[John_Mc]

When it shuts off is there still fuel in the fuel filter bowl?

Yes.

When you say the five gallon can was bad what does that mean? Are you storing the fuel outside where water can get in? If you store it inside the fuel was probably ok unless it was bad where you bought it.

Stored in my garage (not heated). That's what I'm wondering: was the fuel bad when I bought it?

 

[duffer]

Might have contaminated the fuel lines and rail as well. Might want to add some BioKleen to kill off any residue

 

[dodge man]

You just have one fuel filter correct? Some have two. Tgere is also a chance you have some growth in your tank plugging up the outlet. There are lots of things it could be.

 

[big bubba]

OP: what was the source of the fuel you added when problems began. was it from a high volume vehicle pump, or other? are you using diesel additives that address moisture? good luck, don't panic, it's fuel related

 

[John_Mc]

Only one fuel filter - in the sediment bowl. It is gravity-fed from the tank. Fuel flows well through it when bleeding the lines. No sign of algae or other contamination that I can see, and the fuel seems to flow normally - at least through the low-pressure part of the system. When I crack the fuel lines at the injector, it does weep out of there when cranking the engine.

I do add anti-gel additive in the winter. I'm out of Bio-Kleen. I'll pick some up.

 

[rScotty]

Water can displace diesel in a tank or filter, and bio-crud can clog filters and fittings.... but I've never known diesel fuel itself to go so bad it wouldn't run. It used to be common to use diesel fuel from old questionable tanks after draining off the water layer and "polishing" the fuel by running it through a filter.

I don't have any idea why your NH stops running, but I'd bet it's a fuel supply problem. You say that model NH is all gravity feed, and I'm guessing that means there is no fuel shut-off solenoid to go bad.

Since not having a solenoid eliminates the common fuel shut off solenoid problem, the fuel stoppage almost has to be an air bubble in the fuel line or filter. Check the hose & fittings to and from the tank, filter, fuel pump. Look for wet places. Look especially up where the fuel line exits the fuel tank.

Here's a test I'd do: Next time it stops running, don't even turn off the key, just whip out a wrench and loosen the fitting between the filter and the injector pump. Fuel should run freely out onto the ground and continue running, so be prepared for a spill. If it doesn' run freely there's an air bubble somewhere - probably forjming in one of the lines.
Good Luck,
rScotty

 

[John_Mc]

Water can displace diesel in a tank or filter, and bio-crud can clog filters and fittings.... but I've never known diesel fuel itself to go so bad it wouldn't run. It used to be common to use diesel fuel from old questionable tanks after draining off the water layer and "polishing" the fuel by running it through a filter.

I don't have any idea why your NH stops running, but I'd bet it's a fuel supply problem. You say that model NH is all gravity feed, and I'm guessing that means there is no fuel shut-off solenoid to go bad Since not having a solenoid certainly does eliminate the common fuel shut off solenoid problem, the fuel stoppage almost has to be an air bubble in the fuel line or filter. Check the hose & fittings to and from the tank, filter, fuel pump. Look for wet places. Look especially up where the fuel line exits the fuel tank.

Here's a test I'd do: Next time it stops running, don't even turn off the key, just whip out a wrench and loosen the fitting between the filter and the injector pump. Fuel should run freely out onto the ground and continue running, so be prepared for a spill. If it doesn' run freely there's an air bubble somewhere - probably forming in one of the lines.
Good Luck,
rScotty

It's gravity fed from the tank to the sediment bowl/fuel filter and from there to the injection pump. The test you describe is basically what happens when you bleed the low pressure side of the system (the bleed valve is near the inlet side of the pump.) I get plenty of fuel flow when I crack that valve.

There is a solenoid - that's how the tractor is shut off. I have not looked at that at all yet. I'm leaning away from that as the cause, since it seems odd that it would open briefly, then close. (But I guess stranger things have been known to happen.)

 

[rScotty]

It's gravity fed from the tank to the sediment bowl/fuel filter and from there to the injection pump. The test you describe is basically what happens when you bleed the low pressure side of the system (the bleed valve is near the inlet side of the pump.) I get plenty of fuel flow when I crack that valve.

There is a solenoid - that's how the tractor is shut off. I have not looked at that at all yet. I'm leaning away from that as the cause, since it seems odd that it would open briefly, then close. (But I guess stranger things have been known to happen.)

That's right. Undoing the fitting in that test simply takes the bleed valve itself out of the equation I know of no other way to make sure that valve is not defective and allowing air back into the line to the injector pump.
If I was there doing it myself - as you are - then I might agree that some "feel" to the system indicates that valve is OK. But from here, I can't tell. That's why I thought it best to disconnect or loosen the fitting..

Since there is a solenoid valve, I'd say that solenoid now goes to the top of the list. As a test, you could simply bypass it. Shut down the tractor with the compression release, or adjust the hand throttle to push the injection rack all the way to the off position, or simply clamp the hose.
Luck,
rScotty

 

[thclimer]

My guess is if the solenoid was not opening you would not have been able to bleed the injector lines. You said you visually saw bubbling fuel with the injector nut cracked.

 

[rScotty]

My guess is if the solenoid was not opening you would not have been able to bleed the injector lines. You said you visually saw bubbling fuel with the injector nut cracked.

I think you will see it continue to run until all the fluid is drained from lines above the inlet to the injector pump.
Or if the solenoid is not opening completely it might run OK, then poorly, and eventually stop. It would do the same thing if there was an air leak at the fuel tank fitting.

 

[John_Mc]

I think you will see that run until all the fluid is drained from lines above the inlet to the injector pump.
Even more so if there is an air leak at the tank fitting.

That would explain running for a short while, then dying. But if the fuel flows freely from the tank to the bleed valve at the injector pump inlet, what is stopping the fuel flow?

 

[WinterDeere]

Running for awhile then dying stinks of some clogging in the gravity-fed side of the system, such that gravity feed isn't keeping up with pump demand. Agreed, bio in fuel line could be to blame.

Seeing the sediment bowl run dry while running might prove this out, but if clog is downstream of that, lack of a dry bowl might not prove anything.

 

[rScotty]

That would explain running for a short while, then dying. But if the fuel flows freely from the tank to the bleed valve at the injector pump inlet, what is stopping the fuel flow?

Right now we're all guessing. But to guess at an answer to your question....: An air leak in the bleed valve itself could slowly suck air into the inlet fitting and build up enough of a air bubble in the fuel line to block fuel flow. I'm not saying that is what is happening, but it could be.

To find out for sure if it is a fuel feed problem, you could make up something to hang from the ROPS like mechanics use. Then there's no more guessing about what the problem is, only about where it is.