BX1500 Fuel Injection Pump

[mohamer51]

I have a 2006 BX1500 Kubota. Recently my Lubrication oil level has been getting higher as I use the tractor. I seem to be getting Diesel
fuel in my oil from the Fuel Injection Pump. I have ordered a pump seal kit and plan on installing the kit in the pump when I get it.
I would like to have a procedure for dismantling the pump and putting is back together hopefully with drawings/pictures. A pdf file with such information would be really nice or a copy of a manual with the information would be wonderful. I have searched the internet and forums for information, there is some, some of it is questionable.
If someone could steer me toward some good information I would be very grateful..

 

[Henro]

I have a 2006 BX1500 Kubota. Recently my Lubrication oil level has been getting higher as I use the tractor. I seem to be getting Diesel
fuel in my oil from the Fuel Injection Pump. I have ordered a pump seal kit and plan on installing the kit in the pump when I get it.
I would like to have a procedure for dismantling the pump and putting is back together hopefully with drawings/pictures. A pdf file with such information would be really nice or a copy of a manual with the information would be wonderful. I have searched the internet and forums for information, there is some, some of it is questionable.
If someone could steer me toward some good information I would be very grateful..

First, I would suggest you buy a workshop manual for the tractor.

Second, I would suggest you send the injector pump for rebuild by someone who knows what they are doing. Be sure to take into account any shims that are between the engine block and the pump body.,

Third, I would carefully consider what could cause oil level to increase during operation.

Just me though...Oil floats on water...could you be getting water in the sump? Just a thought...

 

[mohamer51]

First, I would suggest you buy a workshop manual for the tractor.

Second, I would suggest you send the injector pump for rebuild by someone who knows what they are doing. Be sure to take into account any shims that are between the engine block and the pump body.,

Third, I would carefully consider what could cause oil level to increase during operation.

Just me though...Oil floats on water...could you be getting water in the sump? Just a thought...

First, I cannot be sure that the Workshop Manual would have all the information I need.
Second, That is a suggestion, one that I considered a while back.
Third, careful sampling and laboratory analysis indicates Diesel Fuel contamination (no loss of coolant).
Thought-- no barking up the wrong tree...

Thank you for the comments, I appreciate you thoughts,
Mohamer

 

[JerryMT]

I have a 2006 BX1500 Kubota. Recently my Lubrication oil level has been getting higher as I use the tractor. I seem to be getting Diesel
fuel in my oil from the Fuel Injection Pump. I have ordered a pump seal kit and plan on installing the kit in the pump when I get it.
I would like to have a procedure for dismantling the pump and putting is back together hopefully with drawings/pictures. A pdf file with such information would be really nice or a copy of a manual with the information would be wonderful. I have searched the internet and forums for information, there is some, some of it is questionable.
If someone could steer me toward some good information I would be very grateful..

If this machine has a lift pump, they are usually mechanically driven and if the diaphragm tears they can leak diesel into the oil sump. Might want to check that.

 

[Henro]

If this machine has a lift pump, they are usually mechanically driven and if the diaphragm tears they can leak diesel into the oil sump. Might want to check that.

My guess it is an electric fuel pump, similar to what is used on the BX1800 and BX2200, but do not know for sure...

 

[Mark_BX25D]

An injection pump is a different animal. Rebuilding one requires specialized knowledge and specialized tools. It's really not for even an advanced DIYer.

Agree with checkign for a mechanical lift pump. If you have one, that's the number 1 suspect, and an easy job for most of us.

 

[North Idaho Wolfman]

How does it start and run?
If it starts quickly and easily, your chances of it being the injection pump are highly unlikely.
If it runs with good power, again, your chances of it being the injection pump are highly unlikely.
No manual lift pump on that model so that's out.

The WSM (aka Service Manual) for that model does not show or explain how to rebuild the injection pump.
If you notice the top of the injection pump have 4 Security Torx head screws to remove the delivery valves, you have to have the proper test equipment to set the curve on that style of pump.
There is no seal kit for the high pressure side ( which is what would leak in to the inside of the engine) it's a tolerance fit seal nothing more.
Rebuilding Injection pumps on there is NOT a DYI project period!

Now more commonly (especially if your getting any smoke out of the engine or it's not starting or running properly would be that you have an injector that is leaking down.
So it might be in your best interest to pull them and have them tested and replaced / rebuilt also.

You options for a rebuilt or new pump are limited, that engine is not a common model.

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Or what I would do is pull it, remove and save all shims under the Injection pump, and then send the pump here to be tested and rebuilt.

Home

Oregon Fuel Injection specializes in the repair of diesel fuel injection systems, replacement diesel parts, performance parts, drive-in service, repairs and diagnostics.

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[mohamer51]

If this machine has a lift pump, they are usually mechanically driven and if the diaphragm tears they can leak diesel into the oil sump. Might want to check that.

The BX1500 has a lift pump, it is Electric, no chance that it is at fault.

 

[mohamer51]

How does it start and run?
If it starts quickly and easily, your chances of it being the injection pump are highly unlikely.
If it runs with good power, again, your chances of it being the injection pump are highly unlikely.
No manual lift pump on that model so that's out.

The WSM (aka Service Manual) for that model does not show or explain how to rebuild the injection pump.
If you notice the top of the injection pump have 4 Security Torx head screws to remove the delivery valves, you have to have the proper test equipment to set the curve on that style of pump.
There is no seal kit for the high pressure side ( which is what would leak in to the inside of the engine) it's a tolerance fit seal nothing more.
Rebuilding Injection pumps on there is NOT a DYI project period!

Now more commonly (especially if your getting any smoke out of the engine or it's not starting or running properly would be that you have an injector that is leaking down.
So it might be in your best interest to pull them and have them tested and replaced / rebuilt also.

You options for a rebuilt or new pump are limited, that engine is not a common model.

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Fuel Injection Pump 16001-51012 for Kubota Engine Z602

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Or what I would do is pull it, remove and save all shims under the Injection pump, and then send the pump here to be tested and rebuilt.

Home

Oregon Fuel Injection specializes in the repair of diesel fuel injection systems, replacement diesel parts, performance parts, drive-in service, repairs and diagnostics.

oregonfuelinjection.com

The engine starts and runs perfectly, the injectors are fine.
I have a rebuild kit on the way, they are readily available.
I have worked on several diesel injection pumps in the past, not this specific one but I don't think I will have a problem pulling it apart, repairing it, and remounting it on the engine.

 

[mohamer51]

As the North Idaho Wolfman mentioned, the WSM from Kubota has no information on rebuilding the Fuel Injection Pump on the Kubota BX1500. Kubota wants one to purchase a new Injection pump if there is a problem with the pump. New or rebuilt pumps do not come cheap, Messicks wants $910.00 or so for one.
A rebuild kit for the Injection Pump is less that 1/10 of that price. Other rebuilt pumps are available at around 1/2 Messicks price. My original post was an effort to find information on proceedures to rebuild the Fuel Injection Pump on my Kubota BX 1500. I have found some information online, some of it is rather sketchy, I was hoping I could get some help here. I am still waiting.

Thank You all for your responses
Mohamer

 

[mohamer51]

Well Folks, I removed the Fuel Injection Pump, took it totally apart, checked it out, put it back together, it runs great!!!!
What was wrong, you may ask?????
The only point of concern I had was the lower o-ring on the pump Barrel, both pumps. Both o-rings appeared to be too loose when inserted into the pump housing. I checked the size of the housing (ID) and the Barrel size (OD/o-ring groove) and determine that a o-ring the same ID but fatter was needed. I tried it and it went together very well. So, I put the bigger o-rings on both Barrel lower o-ring grooves.

I cleaned everything in my Ultrasonic Cleaner, reassembled it all, the engine runs very well, checked exhaust temperature on both cylinders, they are the same when running, timing looks very good too.

Now I will watch my Sump level to see if it is stable as it used to be.

Thank You All for Your Comments,
Mohamer

 

[Henro]

Well Folks, I removed the Fuel Injection Pump, took it totally apart, checked it out, put it back together, it runs great!!!!
What was wrong, you may ask?????
The only point of concern I had was the lower o-ring on the pump Barrel, both pumps. Both o-rings appeared to be too loose when inserted into the pump housing. I checked the size of the housing (ID) and the Barrel size (OD/o-ring groove) and determine that a o-ring the same ID but fatter was needed. I tried it and it went together very well. So, I put the bigger o-rings on both Barrel lower o-ring grooves.

I cleaned everything in my Ultrasonic Cleaner, reassembled it all, the engine runs very well, checked exhaust temperature on both cylinders, they are the same when running, timing looks very good too.

Now I will watch my Sump level to see if it is stable as it used to be.

Thank You All for Your Comments,
Mohamer

Thanks for reporting back. Glad to hear of your success.

Could you share what taking the pump totally apart actually means?

Asking because I know nothing about the internals of these pumps, but have read that timing is a serious consideration, and that they must be assembled properly, or otherwise the engine will not run right.

Also read it is possible to shift something inside the pump, if you loosen the fuel lines feeding the injectors, at the pump end, improperly. And the tractor will not run correctly anymore. This is the reason I am asking.

Since final timing is set by the factory using shims between the pump and the engine block, it would seem to me there is some standard used to make all pumps the same when manufactured, and that is why shims are used in the final setup at the factory.

When reading your post about your success, the question that popped into my mind was: "How did he get everything back together the same as it was before disassembly?"

 

[mohamer51]

UPDATE
My Kubota is still running great!! The oil sump is not collecting diesel fuel, all is well.
What taking the fuel injection pump completely apart means is, exactly what it says. I diassembled the entire pump system. As stated above, I have worked on a lot of fuel injection pumps, all of the previous ones were LARGER than this one. I used proper proceedures that insures proper re-assembly.
I totally dissassembled it to inspect all parts to insure the integrity of all parts.
After a year and 1/2 I think we can call the operation a success.

Merry Christmas to all AND
Happy New Year 2025
John