Kubota RTV 1140 transfer pump issues.

[plasmaguy]

Hello everyone. My Kubota is having fueling problems. My first diagnosis was that cam driven transfer pump had failed. Machine has 2,900 hours. I replaced it and problem solved. Several months passed and the issues came back. I tried an electric 12V transfer pump and problem solved.
Now as you're guessing the problem has re-surfaced a third time now. A retired diesel mechanic, Detroit, Cummin, CAT , guy is say I need to measure to pressure on the discharge side of the injection pump. Don't have the gauges required and may take to the dealer.

I wanted to ask on this forum beforehand.

Thank you all.

Tom

 

[thepumpguysc]

The inj pump only needs 6-8 psi to operate correctly..
The supply pumps seem rather cheap to buy..
Do u run the tank dry often.?
THAT would ruin a pump before it’s time..

 

[plasmaguy]

Never runs dry. 2900 hours.

Thanks for your help.

Tom

 

[thepumpguysc]

I’m trying to figure out WHY the electric pumps are failing.. R they cheap 10.00 pumps from China.??
R the pistons seizing up from lack of lubrication.?? Or the diaphragm tearing for the same reason.??

 

[plasmaguy]

I’m trying to figure out WHY the electric pumps are failing.. R they cheap 10.00 pumps from China.??
R the pistons seizing up from lack of lubrication.?? Or the diaphragm tearing for the same reason.??

Chinesieum pumps

 

[plasmaguy]

Chinesieum pumps

Either Napa or O'reilly, their electric transfer pumps come from China also.

 

[plasmaguy]

Update time. I installed a new electric transfer pump and in have no fuel exiting the injectors.
The fuel solenoid is new also.

The only thing I think that can have failed is the injection pump.

 

[MTGreen]

Is there an air bleeding procedure on this model?
No fuel out 1 injector or all injectors?
Are you certain the solenoid is activating?
Did you disconnect the feed line at the injection pump to make sure you are getting fuel to the injection pump from the transfer pump?

 

[thepumpguysc]

Yup.. as MTGREEN ASKED, MAKE SURE u have fuel UP TO the inj pump.. put the throttle in the wide open throttle position and crank the engine..
U can leave the steel lines off of the pump.
Let us know what happens..
Good luck

 

[plasmaguy]

Yup.. as MTGREEN ASKED, MAKE SURE u have fuel UP TO the inj pump.. put the throttle in the wide open throttle position and crank the engine..
U can leave the steel lines off of the pump.
Let us know what happens..
Good luck

Thanks guys.

I have fuel coming to the pump. I will check tomorrow and report back.

 

[plasmaguy]

Is there an air bleeding procedure on this model?
No fuel out 1 injector or all injectors?
Are you certain the solenoid is activating?
Did you disconnect the feed line at the injection pump to make sure you are getting fuel to the injection pump from the transfer pump?

MTGreen, yes sir, the new solenoid is working. We have fuel at the pump. I have all three nuts at that connect injectors broken lose also.

 

[thepumpguysc]

On that mdl tractor, does it have a cover plate right below the inj pump.??
Usually has 4-10mm bolts holding it on..
U can remove the plate and see if the pump control rack is moving or if it’s stuck..
OR.. if u have the shut off solenoid that screws into the inj pump hsg., u can unscrew the solenoid and reach in with a pick or pencil to feel if it’s moving..

 

[plasmaguy]

Pump guy

Thank you for your help. I haven't had a chance to open it up yet.

Attached is a picture of the pump.

 

[plasmaguy]

On that mdl tractor, does it have a cover plate right below the inj pump.??
Usually has 4-10mm bolts holding it on..
U can remove the plate and see if the pump control rack is moving or if it’s stuck..
OR.. if u have the shut off solenoid that screws into the inj pump hsg., u can unscrew the solenoid and reach in with a pick or pencil to feel if it’s moving..

On that mdl tractor, does it have a cover plate right below the inj pump.??
Usually has 4-10mm bolts holding it on..
U can remove the plate and see if the pump control rack is moving or if it’s stuck..
OR.. if u have the shut off solenoid that screws into the inj pump hsg., u can unscrew the solenoid and reach in with a pick or pencil to feel if it’s moving..

thepumpguysc,​

I am getting back on this project.

We have installed a rebuilt the fuel injection pump. We are still not getting fuel to the injectors all the time.
1. We have the solenoid removed and the rack is in the open position. I think the rack is always open unless the solenoid in mounted and then turns fuel off.
2. We have fuel coming to the pump with an electric fuel pump.

We are getting fuel to the 1st and 2nd injectors but none to the 3rd. The lines are removed.

With the fuel pedal pressed to the floor there's little change.

I am sure open to any suggestions.

Thanks,

Tom

 

[thepumpguysc]

So u changed the pump.??
And still have the problem.??
Common sense tells me, it’s not the pump..
Take the pump back out and check the lobes on the camshaft that drives the pump..

 

[plasmaguy]

So u changed the pump.??
And still have the problem.??
Common sense tells me, it’s not the pump..
Take the pump back out and check the lobes on the camshaft that drives the pump..

We are using an electric lift pump, the cam operated pump is out of the equation. There's plenty of fuel going to the pump. The solenoid is out and the rack is in the run position.

 

[thepumpguysc]

Sorry, my mistake.. I was talking about the inj pump..
Pull it back out and check the cam lobe in the engine that operates it.
& while the inj pump is out, make sure the roller on the bottom of the inj. pump has spring tension on it..
It’s possible that if the pump has sat on the shelf, the plunger in the cyl that’s not pumping, is stuck in the up position..
You can tell by the roller not having spring force in the down position.
Also make sure the inj pump control rack will move left and right very easily..

 

[plasmaguy]

Sorry, my mistake.. I was talking about the inj pump..
Pull it back out and check the cam lobe in the engine that operates it.
& while the inj pump is out, make sure the roller on the bottom of the inj. pump has spring tension on it..
It’s possible that if the pump has sat on the shelf, the plunger in the cyl that’s not pumping, is stuck in the up position..
You can tell by the roller not having spring force in the down position.
Also make sure the inj pump control rack will move left and right very easily..

Hello Pumpguysc,

We're starting back on it next week. The spring tension is an interesting point. I will let you know what we find out.

Thank you sir.
Happy Easter.

Tom