Kubota BX24 Injector pump problem

[cal1]

My owners manual says to change the fuel filters every 500 hours so when the local dealer tried to tell me to change them every year. I thought "yea right, just trying to make extra $". Seems like you guys are saying once a year also.

My hourly use on an annual basis is really low, probably less than 100 hours. Should I be changing once a year?

 

[Max Power]

My owners manual says to change the fuel filters every 500 hours so when the local dealer tried to tell me to change them every year. I thought "yea right, just trying to make extra $". Seems like you guys are saying once a year also.

My hourly use on an annual basis is really low, probably less than 100 hours. Should I be changing once a year?

...a fuel stabilizer might be of more benefit. most of these units have a clear sediment bowel. Diesel fuel should be clean and bright and this is visible in the sediment bowel. So if it is clean and bright and no sediment then what exactly will you accomplish by changing the fuel filter.

I personally don't believe in over servicing. I need a reason to exceed the manufacturers recommendations. ...like dirty fuel or really old fuel or visible water.

cheers

 

[Deano]

My owners manual says to change the fuel filters every 500 hours so when the local dealer tried to tell me to change them every year. I thought "yea right, just trying to make extra $". Seems like you guys are saying once a year also.

My hourly use on an annual basis is really low, probably less than 100 hours. Should I be changing once a year?

I say yes. I change mine every 100 hours regardless. Cheap insurance! :thumbsup:

Deano

 

[Max Power]

I say yes. I change mine every 100 hours regardless. Cheap insurance! :thumbsup:

Deano

lol

good tires and windshield wipers are good insurance.

I don't put fuel filters in that category. If you have bad fuel you may need to change the filter every week. If you have good fuel then you risk introducing dirt into the system.

...if it makes you feel better go for it.

 

[dodge man]

BX's have no filter bowl. They also have very small filters. I'd agree with changing them more often, maybe every 100 to 200 hours.

 

[kuboman]

My owners manual says to change the fuel filters every 500 hours so when the local dealer tried to tell me to change them every year. I thought "yea right, just trying to make extra $". Seems like you guys are saying once a year also.

My hourly use on an annual basis is really low, probably less than 100 hours. Should I be changing once a year?

Once a year may not be necessary, depends on the quality of the fuel. Just remember every time you open the fuel system there is the potential for dirt to get in.

 

[kuboman]

amen ...... bio-diesel is not ready for the market.

here is the Kubota bulletin on it.

Kubota Engine America - Compact Diesel Engines

So why are we putting this crap in our diesel. There is another thread somewhere on this forum about fuel additives. Yet another reason to use a good additive.

 

[Chilly807]

As to the relative performance of the two types of injection system...

Indirect injection means only that the fuel spray does not go directly into the combustion chamber, but rather into a pre-combustion chamber. There is still a high pressure spray of atomized fuel, but it is in a fairly narrow cone shape. This is because of the nozzle design, called a "pintle-type" nozzle.

With a direct injection engine, the tip of the injector actually extends slightly into the combustion chamber, and has multiple small holes (usually 4 or 5) for the fuel to spray through. It will be seen as a fine mist radially distributed in 4 or 5 sprays around the tip of the injector. This is called a multi-hole nozzle.

It's possible there is still a bit of air left in the hard pipe injection lines, which is why there is no visible spray into the mason jar. A small engine like this doesn't move a lot of fuel, even at start-up when it gets max volume delivery.

It may take 20 seconds of cranking time to actually get fuel out of the new injector until the system is fully bled. I would try loosening the new injector on the fuel line by a few turns, then crank the engine until you get fuel coming out where the line is loose. Stop cranking and immediately re-tighten the line and try again for at least 10-15 seconds. If nothing then, re-loosen the line and repeat the process.

It's possible you have injection pump problems, but the fact that it did this before and then started and ran fine after you fiddled with it, then re-occurred makes me wonder if it's not simply getting airlocked for some reason.

The injection pump has what are called "delivery valves" in the top of the pump which act as check valves to maintain a certain line pressure between injection cycles to reduce lag time when building enough pressure to open the injectors for each injection event. If the pump can make enough pressure to open these, and yet not enough to operate the injector, it's possible but not a common defect. In fact, I've never seen it happen before.

And for all the elements to be equally worn to this point at the same time is not likely either, ordinarily we'd see one or two damaged and not pumping, but not all of them.

I assume the glow plugs are working correctly?

Sean

 

[fred98050]

UPDATE:


Injector pump is bad and needs to be rebuilt. Internal water corrosion....

History:
The tractor is a 2006, it has 980hrs always garaged and the Kubota fuel filters have been replaced every year as well as air filter. Also used Marvel Mystery Oil religiously (recommended by local dealer)... Never used Biodiesel either.
Might have had some bad fuel at one time, I really don't know why this has happened..It's not like the tractor was ever sitting there unused for more than a few weeks.

What I know now:
- If you see fuel squirting out of injector pump outlets, it doesn't mean that the pump is good. Hook up one (working) spare injector to one line and see if you get some spray. If not. Then the pump isn't working right.
- I am replacing the original fuel filters with better ones and will use water prevention additive.
- I am also relocating the electric fuel pump in engine compartment. Too much of a pain to access (nothing to do with current problem tho)..
-New injector pump cost $860 + tax. Rebuilt cost is between $350 to $800 depending on damages.

 

[radioman]

yikes!! that really gotta hurt on price. Glad you got it figured out though.

I am just glad I use the white bottle of power service. it says it disperses water.

 

[dodge man]

Thats unusual, the first I've heard of a BX main injection pump failing. Kudos to you for ignoring all of us that didn't think that was your problem. Just a pure guess on my part, but maybe you got a little water and shut it down at the exact moment it hit the pump, then it sat for a period of time and did its damage.

A couple of other thoughts. Can you move the lift pump or should it be near the tank like it is from the factory? I don't know the answer to this question.

I wouldn't mess with treating your fuel. Get one of those Mr Funnels and that will catch the water.

 

[Deano]

Thanks for updating us! Please let us know if you rebuild, what they find.

Deano

 

[radioman]

Another thought- On mystery oil website says its for lubrication in diesels, but doesnt say a word about water printed on website. power service does though..

 

[Chilly807]

Have you had the BX from new?

Sean

 

[leonz]

UPDATE:


Injector pump is bad and needs to be rebuilt. Internal water corrosion....

History:
The tractor is a 2006, it has 980hrs always garaged and the Kubota fuel filters have been replaced every year as well as air filter. Also used Marvel Mystery Oil religiously (recommended by local dealer)... Never used Biodiesel either.
Might have had some bad fuel at one time, I really don't know why this has happened..It's not like the tractor was ever sitting there unused for more than a few weeks.

What I know now:
- If you see fuel squirting out of injector pump outlets, it doesn't mean that the pump is good. Hook up one (working) spare injector to one line and see if you get some spray. If not. Then the pump isn't working right.
- I am replacing the original fuel filters with better ones and will use water prevention additive.
- I am also relocating the electric fuel pump in engine compartment. Too much of a pain to access (nothing to do with current problem tho)..
-New injector pump cost $860 + tax. Rebuilt cost is between $350 to $800 depending on damages.

Hello Fred,

Sorry to hear about the injection pump , AAAYYYY CARAMBA LUCY!!!!!

Candidly it is better to buy the new pump.

I would contact Foley foley engine and purchase the mechanical lift pump for this engine-yes they do have one that is driven off the engine drive train.

In for a penny in for a pound, as you have to replace/rebuild the injection pump I would strongly suggest that you install a Racor diesel fuel filter to prevent any water from entering the injection pump-between the fuel centrifuge and the cartridge fitration it stops 100% percent of the water by expanding to the point where it totally blocks the flow of fuel and the motor dies-its cheap insurance for sure as a 2 micron filter will filter out thousands of gallons of fuel before it needs replacing or water totally clogs the filter.

All I can tell you is they work and I have a Racor centrifugal filter on my kerosene tank and I know I have no problems with fuel now and will not have any problems with the boiler in the future because of crap and water in the kerosene fuel.

I would replace the fuel tubing with the Racor Reinforced Fuel Tubing as well as it(thr old tubing) will collapse on you due to the pressure gradient created by the vacuum of the electric pump.

 

[Stradbash]

I guess it's time for me to post a picture or two of my Racor fuel filter installation... Mine is just outside the frame of the tractor on the left side and just a bit in front of the floor pan on my BX-25. I was able to relocate the lift pump to between the Racor and the injector pump without messing with the wiring. I also left the original filter in engine compartment between the lift pump and the injector pump to protect the injector pump in the event that lift pump fails as suggested by Neil Messick. So..., Fuel tank, Racor, lift pump, factory fuel filter, injector pump. It is my understanding that (if the tractor has one) that it is best to have the lift pump after the Racor fuel filter so you do not promote emulsification (think mixing) of the fuel and any available water. I'll plan to take the photos this weekend when I'm out switching from leaf collecting to snow plowing mode... :thumbsup:

 

[leonz]

Yay!!!!!


I love it when a plan comes together!!:thumbsup:

 

[ccsial]

The indirect injection fuel nozzle allows fuel to pass with no, I repeat no restrictions!!!!! :

This is not true on my Ford 1910. The dealer tested my nozzels in a unit that measures the pressure at which they crack open.

On a system like the 1910 if the injector pump is weak the injectors will not open. I know this from experience.

I Don't know if this is true on Kubota's.

 

[Chilly807]

This is not true on my Ford 1910. The dealer tested my nozzels in a unit that measures the pressure at which they crack open.

On a system like the 1910 if the injector pump is weak the injectors will not open.

I Don't know if this is true on Kubota's.

I would agree with you.

Kubota is the same.

Sean

 

[Stradbash]

OK, here are a few photos I took a while ago. The first is the way I plumbed all the new stuff and the second is the filter installed on the tractor. The lift pump is behind the new mounting plate for the filter and toward the front of the tractor. I can try to take a pic of that if anyone needs it. The new mounting plate required no new holes in the frame. The bolt that is in front of the filter goes through the hole that was in the frame for either a steering or fuel line clamp. (I'll check that later). The small one near the top left corner of the mounting plate is a clamp that grabs the top edge of the frame. The wire for the fuel pump runs just under the fan shroud (I made a little holder to keep it there) and to the re-located pump. No more getting under the tractor and taking off the skid plate to change the fuel filter!