Oil & Fuel Kubota BX1850 sputters under load, fuel injector problem?

[citislycker]

Hi folks,

I'm a reformed city slicker from southern California who finally found Jesus, escaped the concrete jungle, and I now find myself in the Northwest with 15 acres, 12 horses, 2 goats, a llama (don't ask), and more cats and chickens than I can swear at.

This new life also includes a Kubota BX1850 that we probably ask too much of. Most recently, one of the farm hands (okay, me) had it roll over on it's side when the loader was fully raised and only one of the back tires sank into some loose sand. No apparent damage; I quickly shut off the engine and flipped it back up.

I let it "rest" for a bit, did a quick visual inspection, checked the oil, crossed my fingers, and fired it up. There was a little smoke when it started, but no other immediate symptoms indicating any trouble.

Fast forward about ten hours without incident, and then the engine starts wheezing and stumbling a bit when under load. Over the next few hours, this gets worse. RPMs randomly drop for a few seconds, and then come back to full speed (3,100 rpm). It happens less frequently if we operate at only 2,000 rpm, but it's still happening.

I have since changed fuel and air filters, and put new screw type hose clamps on the fuel lines. The fuel filter has since completely filled with fuel, and the tractor has run about 20 hours since changing all filters. However, it still coughs and sputters when under load.

Okay gurus. Karma is kicking my but for all those years of jokes about overalls and victim sheep. Seriously, I need some guidance here... I've built race trucks and airplanes from the ground up, but diesel tractors are new to me...

Should I be going after the injectors (3 of 'em on this li'l engine), hunting down rogue air in the sytem between the filter and the injectors, or is there a setting I can tweak on the fuel pump? What is the procedure for bleeding air from the fuel system at the engine? Is there a compression release valve or lever? Am I totally on the wrong path here?

I'm at your mercy.

 

[kevinj]

Did you change BOTH fuel filters???

 

[radioman]

the BX's bleeds the air out automatically, not like bigger engines. There seems to be no feul pump tweaks that i know of.

I agree that you may have missed one feul filter, its under the BX before the pump. I would replace that, blow the line going in tank to make sure inlet is clear. Due to odd shape of feul tank, you can't see if it blocked or not.
Also I would run the tractor with hood open and watch the shutoff soleniod. chances are either wire got shorted out from rollover or one of saftey swtiches got knocked loose. Did you know that if you have an older BX seat, it makes you lean forward making saftey switch kick in more easily?

Its a good thing you replaced air filter and on i suspect you already replaced the feul filter by side of engine, the easiest one to spot, just do one more underneath.

check those things and lt us know how it turns out and we will go from there.

 

[leonz]

Hi folks,

I'm a reformed city slicker from southern California who finally found Jesus, escaped the concrete jungle, and I now find myself in the Northwest with 15 acres, 12 horses, 2 goats, a llama (don't ask), and more cats and chickens than I can swear at.

This new life also includes a Kubota BX1850 that we probably ask too much of. Most recently, one of the farm hands (okay, me) had it roll over on it's side when the loader was fully raised and only one of the back tires sank into some loose sand. No apparent damage; I quickly shut off the engine and flipped it back up.

I let it "rest" for a bit, did a quick visual inspection, checked the oil, crossed my fingers, and fired it up. There was a little smoke when it started, but no other immediate symptoms indicating any trouble.

Fast forward about ten hours without incident, and then the engine starts wheezing and stumbling a bit when under load. Over the next few hours, this gets worse. RPMs randomly drop for a few seconds, and then come back to full speed (3,100 rpm). It happens less frequently if we operate at only 2,000 rpm, but it's still happening.

I have since changed fuel and air filters, and put new screw type hose clamps on the fuel lines. The fuel filter has since completely filled with fuel, and the tractor has run about 20 hours since changing all filters. However, it still coughs and sputters when under load.

Okay gurus. Karma is kicking my but for all those years of jokes about overalls and victim sheep. Seriously, I need some guidance here... I've built race trucks and airplanes from the ground up, but diesel tractors are new to me...

Should I be going after the injectors (3 of 'em on this li'l engine), hunting down rogue air in the sytem between the filter and the injectors, or is there a setting I can tweak on the fuel pump? What is the procedure for bleeding air from the fuel system at the engine? Is there a compression release valve or lever? Am I totally on the wrong path here?

I'm at your mercy.

First:

Your diesel engine is indirect injected, and thank you Jesus for that anyway.


You have injection nozzles not injectors;


Are you sure you do not have water in the diesel fuel?


If you were working in an incline or decline and the fuel tank is not full

it is entirely possible you have air in the fuel system and it has to be bled out period.



Pop the hood open and leave it to cool down for an hour or so;

crack the first flare nut on the first cylinder and pull up on the steel fuel line a tiny bit to

break the seal (17 MM)I think?, start the engine and let it run at idle and the air will purge

form the first fuel line repeat the process for the other two-one at a time!!!


If you continue to have the problem it has to be a plugged fuel line or one of the gaskets:

did you change both fuel filters?


You should invest in a Racor model 1100 centrifugal fuel filter to solve all your fuel problems

and you can eliminate the kubota filters as an issue permanently by leaving the drop in

cartridges out if you wish to.


The Racor unit has a clear sediment bowl below the centrifuge which allows the water and

crud to settle out and you can drain it daily as well with the drain valve at the bottom of the

bowl, it also has internal check valves to hold fuel and stop air from entering the fuel

system when changing the drop in filter and o-ring gasket.


leonz

 

[funwithahoe]

Seems like your real problem here is owning 12 horses - Without them you junk the old 'Bota and buy a new "M" series 'Bota and call it a day!!!:laughing:

 

[Johndeere3720]

Seems like your real problem here is owning 12 horses - Without them you junk the old 'Bota and buy a new "M" series 'Bota and call it a day!!!:laughing:

My grandpa has 75 horses! beat that one. And, on only 5 acres. Thats over an acre of just barn.

 

[redharley]

After 20 hrs of operating I doubt you have any air in the system,Most likly water or dirt in TANK. Do not forget there are 2 filters as mentioned before Change them BOTH. Injector pump and nozzle's very seltom look eveywhere else before. Wiring to shutdown selinoid is a good place to look. Good luck

 

[citislycker]

Gent's, I can't thank you all enough!!

I didn't realize there was a 2nd fuel filter. Of course, I'll change that pronto! I'll also bleed each of the 3 fuel lines at the top of the engine.

Hopefully, that will be it. I'll be at it tomorrow evening, and look forward to reporting back here with the results.