v2203 fuel starved

[tnc110]

this is atually on a 08 bobcat 335 with kubota v2203 engine.
machine is starving for fuel. I replaced the fuel filter, filled fuel filter with diesel 911, replaced lift pump. still fuel starved...or so it seams. if I squeeze the fuel primer bulb while it it running it clears up for a few seconds. removing fuel line and squeezing primer bulb ,fuel flows freely.

as soon as I replaced the lift pump the machine ran great for 5 minutes or so then fuel starvation slowly came back.

not sure if the engine temp is a factor.
maybe cam that runs lift pump is worm?

any ideas?

 

[tnc110]

pick up tube looks fine. tried running with fuel cap off, still no luck

 

[rentthis]

My first guess is trash in the fuel tank.

 

[Roadworthy]

Disconnect fuel line just after tank. Attempt to gravity drain into a bucket. Fuel should flow freely. If flow is REALLY slow you've probably found your problem.

 

[tnc110]

My first guess is trash in the fuel tank.

I checked the screen on the pickup tube, it was spotless

 

[JerryMT]

Check entire fuel delivery system, piece by piece, from the tank to the injector pump. When you get to the lift pump, check it while cranking the engine. Is this a gravity feed system to the lift pump? Make sure that the return to tank line from the IP is clear.

 

[Russell King]

Is there a water separator in the system that could be full of water and limiting fuel flow?

 

[tnc110]

Is there a water separator in the system that could be full of water and limiting fuel flow?

I have bypassed every part of the fuel system and used an electric pump to pump fuel directly into the injector pump and I'm still having issues when the machine gets hot. Tomorrow I'm going to get a fuel gauge and check the fuel pressures going into the injector pump when cold vs when hot. Seems very odd that the engine runs poorly when hot. It takes a good 15 minutes of running hard to get it to run poorly but once it starts running poorly it does not recover.

 

[JerryMT]

Difficulty running with an engine at operating temperature and starting with a warm engine can mean a worn IP.

 

[Russell King]

I have bypassed every part of the fuel system and used an electric pump to pump fuel directly into the injector pump and I'm still having issues when the machine gets hot. Tomorrow I'm going to get a fuel gauge and check the fuel pressures going into the injector pump when cold vs when hot. Seems very odd that the engine runs poorly when hot. It takes a good 15 minutes of running hard to get it to run poorly but once it starts running poorly it does not recover.

Then I think you need to stop chasing fuel problems and start chasing the “runs bad when hot or warm” problem.
My only suggestion there is to make sure it is not overheating by some alternative measurement method (infrared thermometer or mechanical temperature gauge or thermometer in the radiator).

 

[tnc110]

very odd that we have 2 machines with the same issue. now my deere/yanmar tractor is acting up. starting to think there is an issue with the fuel source. we have a bulk tank serviced by a fuel company.

 

[Russell King]

When you did the bypass test did you use fuel from the (local) fuel tank or did you get it fresh from the “gas station“?

If you used your same fuel supply you may want to repeat the test with fuel from a different supply. That would show if the fuel is the cause?

 

[tnc110]

same fuel
will try again

is there a spot in the return that could be causing issue? I understand some fuel systems have an orifice, for lack of a better term, in the return line.

When you did the bypass test did you use fuel from the (local) fuel tank or did you get it fresh from the “gas station“?

If you used your same fuel supply you may want to repeat the test with fuel from a different supply. That would show if the fuel is the cause?

 

[tnc110]

We had the state come out and test our fuel. It is full of gasoline.

How much damage was done to my engine running fuel with gas?

 

[JerryMT]

We had the state come out and test our fuel. It is full of gasoline.

How much damage was done to my engine running fuel with gas?

Sounds like you need to have a discussion with your fuel supplier first, then the local Bobcat dealer regarding an engine check out. Glad you found the cause. That's the first time I heard of this type of problem.

 

[Russell King]

Glad you found the root cause of the trouble.

I don’t think you have damaged your tractor.