Fuel Starvation ?

[bsmart]

I've been using a 1999 Kubota B21 for several days now. Every time it's put under a reasonably heavy load it acts like it is starving for fuel. Especially if going up a grade of any size and length. It seems to be more prevalent if the fuel tank isn't completely full.
The engine bogs down and on occasion it has died. It is operating at about 7000 ft. elevation if that matters. It came from about sea level where it spent most of it's life until a couple of years ago.
Ideas??

 

[North Idaho Wolfman]

Fuel filter, Air cleaner, Hydraulic filters and fluid, and not backing off the HST pedal when your climbing a grade, will all cause the symptoms you are explaining.

 

[MapleLeafFarmer]

X2 from above.

Also, more info like:

- what RPM are you operating
- what gear you are in
- define reasonably heavy load a little more plse.

If RPM low it could bog, if gear to high for job it could bog, if load is too heavy and you be asking that tractor to do more than designed it could bog. Often operators doing combination of all 3.

 

[Russell King]

Is the fuel tank above the injector pump or lower with a lift pump? If the latter, is the lift pump putting out enough fuel?

 

[bsmart]

Is the fuel tank above the injector pump or lower with a lift pump? If the latter, is the lift pump putting out enough fuel?

Good info from all..thanks.
How many operating hours can be put on this little engine, if it is maintained properly, before it becomes a rebuild concern?

 

[GreensvilleJay]

'loaded' question though 1,000s would be my guess.
I just went 1000.1 on my 5 year old BX23S and it's running same as day one.

 

[North Idaho Wolfman]

Good info from all..thanks.
How many operating hours can be put on this little engine, if it is maintained properly, before it becomes a rebuild concern?

I have several 4000 hour engines that are still well within spec.

You can check if the lift pump is working by removing the fuel return line off of the side of the injection pump, temp cap that line.
Extend a new line off the vent fitting to go above the fuel tank fuel level.
Start it, let it idle, and check for pulsed fuel coming out of the return line.
No flow bad lift pump.
And yes 7000ft does effect it's performance, the only cure to that is to add a turbo!

 

[bsmart]

I have several 4000 hour engines that are still well within spec.

You can check if the lift pump is working by removing the fuel return line off of the side of the injection pump, temp cap that line.
Extend a new line off the vent fitting to go above the fuel tank fuel level.
Start it, let it idle, and check for pulsed fuel coming out of the return line.
No flow bad lift pump.
And yes 7000ft does effect it's performance, the only cure to that is to add a turbo!

View attachment 102270

Ah, excellent idea, and great diagram to boot ! Thanks