Fuel Issue?

[Garold Dungy]

I have a Kubota L245DT, It recently started losing power and acted like a fuel filter issue. I changed fuel filter and it started up and ran fine for about 15 min. then started the same thing. I changed fuel lines, drained the tank and blew air through the pit cock fuel valve and another new fuel filter, started up and ran fine for 15 min. and the same thing. This has done the same thing several times, runs fine after it sits a few hours and then loses power after approx. running for 15 min. and acts like it is starved for fuel? Any suggestions?
Thank you

 

[Bulldog]

Have you checked the vent for the tank. Could be plugged up and as you run it a vaccum is created and then it starves itself for fuel.

 

[Lil Foot]

Have you checked the vent for the tank. Could be plugged up and as you run it a vaccum is created and then it starves itself for fuel.

Ditto. My B7100 was doing the same thing. (except it was more like 30min)
When I popped the hood to investigate, my fuel tank was about 1/2 it's original size. Thank god it was a plastic tank; I was able to pop the sides back out, clear the vent, and have had no more trouble.

 

[GWD]

Here is my standard reply when those symptoms are described:

Are you ABSOLUTELY sure that somehow gasoline wasn't added to the diesel fuel tank? (I know you drained the tank and (hopefully) refilled with fresh diesel so this solution is a minimal possibility.)

The other suggestions are valid as well. Just leave off the fuel cap while the tractor is running for a half hour.

If your fuel filter is in a glass case it should always be full to the top with fuel. If there is a bubble of air at the very top of the glass case when the tractor dies then the guys have it right - the tank needs vented.

 

[North Idaho Wolfman]

Another couple possibilities,
Check the air cleaner, lack of air will also effect power.
Check the water level in the radiator too, running hot will also rob power.

 

[Garold Dungy]

Thank you everyone for your good responses. I have actually tried everything mentioned and still have the same issues. Starts and runs great for 15-30 minutes and then lose power and the symptoms seem like fuel starvation,not venting or dirty fuel filter? After it sets and cools down she starts up and runs great again? I may need counseling getting so frustrated.

Thank you!

 

[Whiskey Papa]

What type of diesel? I know you said you drained the system and blew out the lines, but is there any chance of growth inside the tank or lines that could re-plug the line? Is there foaming in the tank at the 15-30 min mark?

 

[Tx Jim]

Thank you everyone for your good responses. I have actually tried everything mentioned and still have the same issues. Starts and runs great for 15-30 minutes and then lose power and the symptoms seem like fuel starvation,not venting or dirty fuel filter? After it sets and cools down she starts up and runs great again? I may need counseling getting so frustrated.

Thank you!

Check that return fuel is going back to tank isn't plugged. If return fuel line/fitting is plugged no diesel engine I know of will run for an extended period of time.

 

[North Idaho Wolfman]

When it losses does it smoke or anything like that?

#1 I would pull the line from the lift pump to the injector pump, while cranking first check that it's moving fuel then put a finger over the end of the line and see if it will push your finger off the line (creates pressure) if it does then the lift pump is fine, if it doesn't then replace the lift pump.

#2 Pull the lines at the injectors and make sure while cranking that the all get fuel, if they do pull the injectors and have them cleaned and checked by an injector shop. The injector might be fouling when it gets hot.

 

[Garold Dungy]

Thank you everyone for your ideas but still have same issue. I am suspecting the fuel shut off valve may be sucking air? I noticed it has been monkeyed with and also when I crack the bleeder valve I see some small bubbles so I am guessing I'm getting air from fuel shut off valve or possibly the filter head. Friend of mine who is a diesel mechanic says shut off valves will suck air and not leak. Also seems to act up after it warms up and get hot. Anyway that is what I am gonna try.

Thank you all again!