L3901 dies suddenly

[fendley]

My L3901 HST has started dying suddenly on me. Occasionally I get the engine rpms surging, but most of the time it is like I turned it off with the key. When this happens, I hear no clicking from the fuel pump.

When it is running properly, and I shut it off via the key, I hear the fuel pump clicking for 10-15 seconds, and then it stops.

I have emptied the fuel/water separator, replaced its screen and o-ring, and replaced the fuel filter.

I'm thinking the next step it to have the dealer look at it, unless there is something else I should try first.

Another note that may assist with the troubleshooting - this does not usually happen until the tractor has run continuously for an hour or more. I have been moving a lot of dirt via the loader, so the engine is up around 2200 rpm. Don't remember the last time the tractor went through a regen cycle.

The tractor has 150 hours on it. Oil and all filters were changed at 50 hours. The fuel filter was changed again (as mentioned above) in the last 5 hours.

I live in SE Georgia, so the weather is very temperate - have been using the tractor in 50-70F when this has been happening.

 

[GreensvilleJay]

I don't know that tractor but this....

When it is running properly, and I shut it off via the key, I hear the fuel pump clicking for 10-15 seconds, and then it stops.

is a concern to me.

I'd expect the fuel pump to STOP when the key is turned OFF !
Others who have an L3901 will know if this is 'normal'. I suspect a bad ignition switch .

 

[sheepfarmer]

Jay, it is normal on an L3560 for the fuel pump to continue for a bit on shutoff. Fuel flow system is different on some of these common rail tractors.

No error message?

Seat switch?

 

[D2Cat]

Not knowing your specific tractor, my first thought is fuel pump relay, or fuel pump itself. Like one of them gets to a certain temp and fails.

How long after it shuts down do you wait before it will start again? Might be something as simple as fuel tank not breathing, so fuel pump creates a vacuum and can't pump.

 

[fendley]

Jay, it is normal on an L3560 for the fuel pump to continue for a bit on shutoff. Fuel flow system is different on some of these common rail tractors.

No error message?

Seat switch?

No error message or warning lights.

I don't think it is the seat switch, but I will play close attention. When I do get a shutdown because of the switch, it is a smooth decline in rpm, and it I sit back on seat, the rpms are restored instantly.

This stall is much more like the engine is struggling for fuel.

 

[fendley]

Not knowing your specific tractor, my first thought is fuel pump relay, or fuel pump itself. Like one of them gets to a certain temp and fails.

How long after it shuts down do you wait before it will start again? Might be something as simple as fuel tank not breathing, so fuel pump creates a vacuum and can't pump.

Usually can get it to restart within 2-3 minutes. I don't crank it longer than 10 seconds, and I wait 30 seconds between attempts.

Usually restarts after 3-4 attempts.

 

[North Idaho Wolfman]

Is it an HST?

 

[sheepfarmer]

Ok doesnt sound like seat switch if it won't start up right away. Does sound like fuel delivery, but you've already done the easy (safe) things. The next time it stalls, look at the water separator bowl and see if it is full. There can be clogs from algae at some connectors near it.

Because some of the other parts of the fuel delivery system are so expensive I'd be inclined to start talking to the dealer at this point. I am not sure where any vent tube for the 3901 fuel tank may be so you could look for a mud dauber nest or other clot as suggested above.

 

[nota4re]

Fuel tank vent?

 

[fendley]

Is it an HST?

Yes, it is an HST

 

[fendley]

Ok doesnt sound like seat switch if it won't start up right away. Does sound like fuel delivery, but you've already done the easy (safe) things. The next time it stalls, look at the water separator bowl and see if it is full. There can be clogs from algae at some connectors near it.

Because some of the other parts of the fuel delivery system are so expensive I'd be inclined to start talking to the dealer at this point. I am not sure where any vent tube for the 3901 fuel tank may be so you could look for a mud dauber nest or other clot as suggested above.

I'll talk to the dealer and schedule a time to drop it off. I just bought an SVL65-2 from him (was just delivered a couple of hours ago, so I will have something to take over the dirt moving duties while the L3901 is out of service.

 

[mdhughes]

Next time it happens, look at the water separator to see if it is full of diesel or not. I had something in my tank on my L3901DT that would cover the outlet hole and would keep diesel from getting out of the tank.

Added 25-Jan-20
When mime did this, I took the hose off going to the water separator and very little volume of diesel came out. After removing what was covering the outlet, the volume of diesel was very high. Have something ready to catch the diesel and a clamp to put on the hose to stop to diesel coming out.

 

[Yooper]

Loosen the fuel cap to allow air to vent in the tank. The vent on your fuel cap may be plugged and not allowing air in the tank creating a vacuum. Simple test to do before you hand it off to the dealer.

 

[fendley]

Loosen the fuel cap to allow air to vent in the tank. The vent on your fuel cap may be plugged and not allowing air in the tank creating a vacuum. Simple test to do before you hand it off to the dealer.

Just to let everyone know that I haven't forgotten the advice; I just haven't run the tractor long enough to get it to die on me. Apparently an hour is not long enough.

 

[fendley]

Another (non)update - tractor still has not died on me. For now I am just going to rack it up to junk in the water separator, cut o-ring on separator that was replaced, and incomplete bleeding that took awhile to get all the air out.

 

[skeets]

Good,, I love happy ever afters

 

[lugbolt]

"Usually" on common rail systems they won't surge, just die--as if you shut the key off. When the rail pressure sensor senses low rail pressure and the SCV can't adjust to keep the rail pressure up high enough to keep it running, it'll just cut the fuel completely, as if you turned the key off. Sometimes it throws a P0087 code, other times not.

 

[chase1992]

Did you ever figure anything out mine was doing this changed fuel filter and tapped on pump for good measure and it was running good for a few weeks now doing it all over I'm not sure if I should pull fuel pump and filter and replace with new or the to dealer

 

[Aufruhrer]

I had the same problem. I checked everything and used all my curse words. Finally, I just pulled every fuse, looked at them, blew on them and put them back. The tractor worked, immediately. This fix makes ZERO sense to me, but I'll take it.

 

[fried1765]

I had the same problem. I checked everything and used all my curse words. Finally, I just pulled every fuse, looked at them, blew on them and put them back. The tractor worked, immediately. This fix makes ZERO sense to me, but I'll take it.

Good to know, ........response to 3 year OP.