F3060 Diesel - Stalling

[jturbo68]

Hi all, First time poster here. Thanks for the assistance.

I have an F3060 that is having a stalling issue.

Last summer, it would intermittently stall out (but not completely) if I was mowing downhill on a steep slope.
It seemed like it was fuel level related.

This spring, it has become much worse. The engine will now stall and recover while sitting still with the PTO disengaged if the throttle is set for high RPM.

One change : I drained most of the fuel out of the tank over the winter.

I tried changing the fuel filter and have also bled the injectors at the engine.
I could feel the engine rhythm changing when I unpressurized each fuel injector ... it seems like the injectors are functional.

Is there a bleeding procedure that I should follow?
Any other thoughts?

Thanks,
John

 

[Stumpy]

Bleed from the lowest point to the highest. Fuel filter, pump, pump fittings, and then the injector fittings. Also advance the throttle to full and if you expect to be there for a while pull the compression release or remove the glow plugs for easier cranking.

Will it run ok for a minute or so before it starts stumbling? There's an electric fuel pump that lifts fuel up from the tank to the injection pump. My guess is that the pump has either failed or it's not getting power. Looking at the parts diagrams I see two identical fuel filters, one before the pump, and one after it, did you get both?

Goto Kubota's website, find the illustrated parts list for your machine and look up fuel filter under fuel systems to see what I'm talking about.

 

[jturbo68]

Stumpy,

Thanks, I had missed the filter closest to the tank. Once I changed that one out, the machine is back to working similar to last year.

One additional Question that I have. The Filter near the fuel tank was mounted with the fuel direction arrow backwards ( The Ridge part of the filter is towards the tank). Does your parts breakout show the filter mounted in that direction? )


Interestingly, it does still seem to lose power when mowing downhill.
Im not sure what to make of that.


I ony had one new fuel filter, which I swapped onto the closest filter to the tank. Ill purchase some new filters and re-bleed the system and see if that changes the behavior.

Thanks for your help.

John

 

[Stumpy]

It doesn't show arrows but it shows a lip on both filters. The end of the filter without the lip is the down stream side of the filter.

http://www.kubota.com/part/partsList.aspx

Punch in your tractor there and you can see for yourself.

If it's still misbehaving check the fuel pump, they're known to cause problems similar to this when they go out. Actually when you bleed the system pull the fuel line off up by the injection pump and flip the key on, see if the lift pump pushes fuel up the line. What may be happening is you're getting a siphon effect which is keeping the injection pump fed normally but when you go down hill the fuel has to siphon up hill which starves it.

 

[jturbo68]

Hi All,

An Update.

I went thru the machine an replaced both Fuel Filters and Bled
the air from each filter, electric fuel pump and injectors.

I continue to have an issue where the machine will run for about 30 - 45 seconds under full load ( PTO Engaged) and then will Stumble for about 10 seconds, before gaining power again.

I have found that if I disengage the PTO before the stumble, wait a few seconds and then re-engage, the mower will continue to run alright.

I am thinking that maybe my fuel pump is not developing enough flow/pressure to keep the machine running under significant load.

When bleeding the system, I used the Electric Fuel pump to purge the air. It seemed to deliver a slow rate of fuel. A trickle basically. Is that the normal quantity that this fuel pump should deliver?


Thanks All,
John

 

[jturbo68]

Hi All,

Any thoughts would be welcome.

I am planning on replacing the inline electric fuel pump, unless anone has a better option. Is there an engine driven fuel pump that could be the problem also?


Thanks

 

[jturbo68]

Just wanted to post a resolution to my issue.


I did end up replacing the lift pump on my F3060 with no change in behavior.

The machine would run fine with the PTO disengaged, but would die after about 15 seconds if the pto was engaged.

As I dismantled the Fuel System further, I found that the draw hose from the tank was partially blocked with old grass that had been drawn into the tube.

Once I got that cleared out and re-primed the system, all is well.

Thanks Everyone for the help.

John

 

[RJW]

I am experiencing the same problem is seems to only stall out after operating for 30 minutes or so. Is your mower still operating after clearing the pick up hose?

 

[coachgeo]

before it gets back to running good, pull the fuel cap off with your ear near buy to see if you hear a wush of air rush in.....

also try running it under same circumstances with fuel cap off and see if it ever even gets to the bogging down/sputter mode.

If one or both of those happens then check to see if cap vent is blocked