Tractor Only Runs With Full Diesel Tank

[Utopia Texas]

5 year old L6060. Maintenance always on time. Always starts and runs great. Beginning of Summer sputtered and stopped after running 2-3 hours starting with full tank. Cleaned mesh filter, replaced spin on filter and filled back up. Started fine and ran another 3-4 hours and stopped again. Since then same thing happens every time. Engine starts and runs great until tank is 3/4 full then stops.

Is this a weak fuel pump that only works with a full tank where gravity pressure helps the pump? Will take in this Fall when the dealership isn’t so swamped. Any ideas?

 

[D2Cat]

5 year old L6060. Maintenance always on time. Always starts and runs great. Beginning of Summer sputtered and stopped after running 2-3 hours starting with full tank. Cleaned mesh filter, replaced spin on filter and filled back up. Started fine and ran another 3-4 hours and stopped again. Since then same thing happens every time. Engine starts and runs great until tank is 3/4 full then stops.

Is this a weak fuel pump that only works with a full tank where gravity pressure helps the pump? Will take in this Fall when the dealership isn’t so swamped. Any ideas?

Maybe the tank vent is partially plugged.

 

[WI_Hedgehog]

Could it be vapor lock, where removing the fuel cap solves the problem?

 

[Utopia Texas]

Will try removing the cap and see what happens. Bad timing on my part. Finished mowing the whole place today and won’t need to use the tractor for a few weeks.

 

[#40Fan]

Siphon out a few gallons to get below 3/4 tank and see what happens.

Do you know if your outlet on the tank is at the bottom or is there a pickup tube that drops in from the top? If there is a pickup tube, and it still doesn't run with less than 3/4, I'd stick a camera in there and make sure the tube is intact.

 

[JonM]

are you actually waiting until the fuel drains down the tube to put more in. the l6060 will click off the pump handle or appear full from addimg via can and it will seem full but its going to be about half full. wait for the fuel to drain to the tank then add more wait add wait add it can be kind of a slow process to fully fuel it. 3 to 4 hours then stopping sounds like your not getting a full fuel fill. 3 to 4 hours is about the runtime of a half tank on a 6060

the gauge will show "F" but your still below full by a good ammount

 

[Utopia Texas]

Yes, When I fill I let it gurgle down 4-5 times until I ca

Siphon out a few gallons to get below 3/4 tank and see what happens.

Do you know if your outlet on the tank is at the bottom or is there a pickup tube that drops in from the top? If there is a pickup tube, and it still doesn't run with less than 3/4, I'd stick a camera in there and make sure the tube is intact.

Will try it out!

 

[North Idaho Wolfman]

Investigate to see if the fuel pump is working!

 

[Killer Bee]

classic symptom of a fuel pickup tube leak inside the tank. equipment vibration and fuel slosh can work on joints and fittings creating air leaks once fuel level drops below the connection. plastic/rubber parts can split and crack. 3/4 gauge indicated may be right where pickup tubing connects to tank top flange inside. seen this personally in steel and plastic fuel tanks.

not saying it can't be lift pump related, however that would typically be more consistent across all fuel levels. could be fuel weight related where enough head pressure pushes through at higher levels however that likely wouldn't keep up with high fuel demands. sounds like the engine runs normally under load then shuts off at a particular level.

good luck!