L4701 Fuel System Issue - Won't Start - Lift Pump Problem?

Cottonmather0

New member
Aug 26, 2018
16
2
3
Fort Bend County, Texas
Have been having problems with my L4701 stalling this week after filling up the fuel tank.

It would lose power and it would stall out, then after sitting 2-3 minutes it would start and run for 3-4 minutes and then die again.

I went to the dealer this morning to get an air filter and a fuel filter. I changed out both but then couldn't get the tractor to start at all after that. I followed the fuel system bleeding procedure in the WSM. The best I could do was a couple of very weak attempts to turn over that never caught on, but for the most park it just cranked with no result. .

I did notice that the new fuel filter filled up with fuel pretty quickly, but that there was no spurting from the bleed valve like I would have expected while running the bleed procedure.

Is this possibly a sign of a bad lift pump and the tractor getting no pressure?

I also cleaned out the water bowl - it was full of gunk, but no water - and it does appear that fuel is getting to the bowl from the tank. It's a fairly consistent stream, a little more than a trickle, but it's not a torrent, either. What should that flow look like?
 
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North Idaho Wolfman

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Jun 9, 2013
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If you had junk in the separator, you more than likely have algae in the system.
Get a good Biocide to treat it.

That's a common rail computer controlled tractor, Save yourself a ton of money and regret and don't randomly go playing with the fuel system. The simplest things can cost you!
Wet the WSM and follow the procedures to check and possibly fix it, and nothing more.
 

Cottonmather0

New member
Aug 26, 2018
16
2
3
Fort Bend County, Texas
If you had junk in the separator, you more than likely have algae in the system.
Get a good Biocide to treat it.

That's a common rail computer controlled tractor, Save yourself a ton of money and regret and don't randomly go playing with the fuel system. The simplest things can cost you!
Wet the WSM and follow the procedures to check and possibly fix it, and nothing more.
Thanks for the advice. I did follow the WSM for instructions for changing the fuel filter and bleeding the system. They seemed a little simplistic, but it says what it says.

I was already planning to try and empty and clean out the fuel tank and see if there is some kind of blockage there that is starving it for fuel. And if that doesn't do the trick, I'm calling the dealer for a service call to get it running. I've about reached the limit of my DIY skills!
 
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brooster

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B5200, BX2360, L3940, Z781i KW
May 15, 2021
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Troy NC
Thanks for the advice. I did follow the WSM for instructions for changing the fuel filter and bleeding the system. They seemed a little simplistic, but it says what it says.

I was already planning to try and empty and clean out the fuel tank and see if there is some kind of blockage there that is starving it for fuel. And if that doesn't do the trick, I'm calling the dealer for a service call to get it running. I've about reached the limit of my DIY skills!
Wolfman knows his stuff, you can trust what he says, and if you think you have a lift pump problem keep an eye on your oil level in the crankcase!
 

North Idaho Wolfman

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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
30,249
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Sandpoint, ID
Wolfman knows his stuff, you can trust what he says, and if you think you have a lift pump problem keep an eye on your oil level in the crankcase!
HAHAHA
The L4701 doesn't use the lift pump like yours, it's a completely different setup.
These fancy new engines will implode if fuel gets into the oil. 😨
 

brooster

Member

Equipment
B5200, BX2360, L3940, Z781i KW
May 15, 2021
68
8
8
Troy NC
HAHAHA
The L4701 doesn't use the lift pump like yours, it's a completely different setup.
These fancy new engines will implode if fuel gets into the oil. 😨
See, learning all the time! Mine is the only diesel I’ve had trouble with, drove big trucks for years but didn’t have troubles like this!
 

Cottonmather0

New member
Aug 26, 2018
16
2
3
Fort Bend County, Texas
Hi -

Just realized I never closed the circle here. My problem was that the water element (ie the metal filter in the jar) was clogged with algae. The jar was slow to fill and when it did, I would get full power, but as soon as all of that fuel was gone I would lose power again until the jar filled back up.

That element was one of the first things I looked at, and I rinsed it off in some kerosene and wiped out the bowl, but that was all I did and then I just assumed it was fine. A couple of weeks later, I was still struggling with it and started looking at pictures of parts when I noticed that a new element was a much brighter and clearer color than mine. I went back and looked at it more closely and that's when saw all of the algae on the inside (which is hard to see because the hole on top is small).

I got a new one at the dealer for ~$15 and put it in and after I got the tractor started I haven't had any trouble since.

Next question is, how do I clear the P0093 code ("major fuel leak")? The tractor was detecting a major loss of fuel pressure - for obvious reasons - but now it's running great and there is obviously no leak, so I want to get rid of that error code.
 
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fried1765

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See, learning all the time! Mine is the only diesel I’ve had trouble with, drove big trucks for years but didn’t have troubles like this!
It is a sign of the times.
We are now "saving the planet". :ROFLMAO:
 

North Idaho Wolfman

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Staff member
Lifetime Member

Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
30,249
6,403
113
Sandpoint, ID
Hi -

Just realized I never closed the circle here. My problem was that the water element (ie the metal filter in the jar) was clogged with algae. The jar was slow to fill and when it did, I would get full power, but as soon as all of that fuel was gone I would lose power again until the jar filled back up.

That element was one of the first things I looked at, and I rinsed it off in some kerosene and wiped out the bowl, but that was all I did and then I just assumed it was fine. A couple of weeks later, I was still struggling with it and started looking at pictures of parts when I noticed that a new element was a much brighter and clearer color than mine. I went back and looked at it more closely and that's when saw all of the algae on the inside (which is hard to see because the hole on top is small).

I got a new one at the dealer for ~$15 and put it in and after I got the tractor started I haven't had any trouble since.

Next question is, how do I clear the P0093 code ("major fuel leak")? The tractor was detecting a major loss of fuel pressure - for obvious reasons - but now it's running great and there is obviously no leak, so I want to get rid of that error code.
Look in the WSM as to how to "clear codes"
Some codes are dealer only resettable codes.
You need to get a good algicide and treat the whole fuel system, and any remain fuel and any future fuel.