kUBOTA 2 CYLINDER Z482 ENGINE

[TRChris]

Hi all,
brief recap, have an engine that was starved of fuel, seemingly the machine regularly serviced but for whatever reason the primary fuel filter just after the tank outlet has never been changed 18 yrs! Installed new filters , pump seems to run fine & when i bled the banjo fuel inlet at the injection pump i get a good squirt of fuel which has no air bubbles,unlike before would take 2 minutes to fill the filter by the inj pump, great i thought, bleed the injection pipes away we go, deep gloom, loads of black smoke, occasionally catches but no run at all. new glow plugs, tested resistance 1.2 ohms, could fuel starvation have caused problems to the injection pump? Have removed injector manifold & removed pump assembly, both plungers good spring resistance, if i disconnect injector supply pipes i do not get much other than a small dribble, please if i disconnect at the injection pump pot outlets, what kind of pressure squirt of fuel should i expect?
I am perplexed, do suspect the injection pump but dont know enough to understand what may have gone wrong.
Chris

 

[Dave_eng]

Do you have throttle wide open when bleeding. Otherwise you are just sending idle levels of fuel out of the injection pump.

Are you certain the glow plugs are getting power. Both during pre-heat and then while cranking.

Dave

 

[Roadworthy]

Lots of black smoke usually indicates low air supply. Check the air filter and be sure no critters have nested in the air intake.

 

[TRChris]

Do you have throttle wide open when bleeding. Otherwise you are just sending idle levels of fuel out of the injection pump.

Are you certain the glow plugs are getting power. Both during pre-heat and then while cranking.

Dave

throttle wide open,glow plugs definately getting power on pre heating never checked whilst cranking, i really need to know if i should get a definite squirt out of injection pump ports with pipes off because i am not !

Thanks for taking the time to reply

 

[TRChris]

Lots of black smoke usually indicates low air supply. Check the air filter and be sure no critters have nested in the air intake.

Thanks for taking the time to reply, no obstruction, even used a hairdryer to breathe warm air directly into the inlet manifold, really confused trying to find how much fuel should be ejected from the removed injector pipe port connections on the top of the inj pump. Chris

 

[North Idaho Wolfman]

Pull the injectors out of the engine.

Then crank it, at full crank and full throttle it should push fuel in a fountain up about 1" to 3" (2.5 to 7.5 cm).

Then if your still not getting Adequate fuel, disconnect the fuel source, and gravity feed the injection pump and check again.

Get back to us on what you find.

 

[thepumpguysc]

Yes Chris, the fuel should squirt a foot out of the pump if u have a good battery.
U said, u took the injection pump out.?? Does the control rack on the pump move freely.??
It needs to move VERY freely..
If u have good supply TO the inj. pump inlet & nothing out..?? u found the problem I would say.