NH LB75B Fuel pump

[DoubleK]

I have a 2003 LB75. All of last summer it started without any problems, once the batteries were replaced. Then, around September, a new problem started to develop. It would get harder and harder to start, meaning that it would turn over fine, but not start. After a bit of cranking, it would sometimes start to catch, and the engine, somewhat firing, would help the starter make the engine turn over faster. However, if you let go of the key, the engine would not run on it's own. Then, trying to crank it again would require a jump or the charger to catch up bringing the batteries to full charge. If you jumped it, the engine would turn over again, and eventually start. Once started, it would run fine with lots of power and no performance issues; just don't turn it off.
Then, last month, 35 degree Wisconsin weather, It wouldn't start at all, even with a jump. It does have the cold weather package (air preheater). I read the owner's manual for cold temp starting. It said you can use ether once the preheater is disconnected. I removed the airfilters to make sure there was no restriction to air flow. The engine was blowing small amounts of soot out of the exhaust, and lots of black smoke when it was 'partially' running, along with the starter, but then the starter over heated and fried.
I replaced the fuel filter and filled it with fuel. I tried to manually prime the mechanical fuel pump, but after 3 minutes of pumping, never noticed any pressure building against the plunger lever. I replaced the started and tried the ether. It ran for 5 seconds, and then stopped. Would not start again...

Question time: I went over a service cd for this unit, but there is no mention of the fuel system, except to 'see dealer'. I know it has a mechanical fuel pump, located right below the fuel filter. Is it possible that the fuel pump is bad? Is there a way to test, or is it better to just replace? $50.
Is there an electrical fuel lift pump on this tractor? I find a listing for one for the LB's but don't know what years it applies to.
Where is the fuel shutoff solenoid located? Again, the manual I have doesn't show it...

Since this issue started before the filter was replaced, I'm not sure that air in the line was an original problem. However, the pump not being able to be manually primed; could that be an indicator that the pump was weak or worn, allowing fuel to leak back into the tank, and not being able to suck it up when needed to?

Would the soot and partial engine running be possibly from the engine and the injectors starving for fuel? I know my Ford diesel wants the right amount of fuel with the right amount of pressure before it wants to run...

Well, that's about it. I did watch a youtube video of a guy starting his LB, 30 degrees. He hit the key and it popped right off. Mine has never done that... even when it was warm out!

Thanks for your time.
By the way, except for the starting issues, I love this machine. We own a Deere 4wd w/front end loader, Kubota 4wd w/loader, NH skid steer and Komatsu dozer. Each one has areas where it out performs all of the others. The Lb is my favorite to run...

 

[thepumpguysc]

• It seems that they put/used 2 different set-ups in the LB75B.. one is a manual lift pump & the other is an electric.. The electric is "part of" the filter head.. the electric part sits on top of the filter head..

The shut off solenoid is on the injection pump.. also 2 diff. ones.. but it'll be where the lines hook up to the pump.
U should make sure u have good flow TO the lift pump.. meaning the tank & outlet filter isn't clogged.
Pull the line coming out of the tank..& check it. OR pull the line from the lift pump going to the filter & crank the engine.. u should get plenty of flow..
The mechanical Lp is only 35.00 w/ free ship on ebay..

 

[DoubleK]

• It seems that they put/used 2 different set-ups in the LB75B.. one is a manual lift pump & the other is an electric.. The electric is "part of" the filter head.. the electric part sits on top of the filter head..

The shut off solenoid is on the injection pump.. also 2 diff. ones.. but it'll be where the lines hook up to the pump.
U should make sure u have good flow TO the lift pump.. meaning the tank & outlet filter isn't clogged.
Pull the line coming out of the tank..& check it. OR pull the line from the lift pump going to the filter & crank the engine.. u should get plenty of flow..
The mechanical Lp is only 35.00 w/ free ship on ebay..

Thanks for the input. When I first got the machine, I drove it for 10 minutes before it shut down and wouldn't start. After some inspection, I put more fuel in it. Then I noticed that the filter was old. When I removed it, it was full of sludge/water. I had to drain the tank and put new fuel and filter in. Ran great. I didn't know that there was another filter on the tank. I'll look for that one and test to see what the flow is. On this unit, isn't the injection pump mounted on the back of the motor, next to the flywheel? Horrible place to try to get to, especially with the front end loader in the down position. I'm used to seeing them in the front...
I also need to make sure that there is 12v current going to the shutoff and that the mice haven't chewed me to less voltage, correct?

I'll be back...

 

[thepumpguysc]

On the back of the motor?? The inj. pump is gear driven off the FRONT timing gears..

 

[NH575E]

I will echo the need to make sure you have no restriction in the lines.

When I got my 575E I fought a problem with it for a week and finally found a little chunk of crap in the banjo fitting at the water separator. On my tractor the lines go first to the water separator then to the lift pump then to the injection pump. I had stuff in the tank I had to clean out and needed the fuel filter changed but that one little bit of stuff in the banjo fitting prevented it from running. The banjo fitting is a right angle bottleneck and I have read of others having a restriction caused by it so check there for sure.

I was able to prime my machine by blowing into the fuel filler at the tank. I used a large rubber stopper with a hole in the center and blew into the tank with an air hose. You may have to improvise with a piece of inner tube or something but it's an easy way to prime the system. With no restriction this will force fuel through to the injection pump. Even with the restriction I was able to get my machine started by doing this but in my case it would run 5 or 10 minutes and shut off.

 

[DoubleK]

On the back of the motor?? The inj. pump is gear driven off the FRONT timing gears..

Sitting on the tractor, left side of engine. On that side, is located the mechanical pump right below the fuel filter. Line goes from the pump to the filter and then it goes to the right, towards the back of the tractor, and therefore the back of the engine to what I believe is the injector pump. Four lines come off the pump and head towards the top of the engine, cross over between the valve covers and go to the injectors.
On the right side of the engine is the starter, towards the back, and right in front of that is the alternator, on the front of the engine. No room for the injector pump.
Engine is a 445T/M2.
Please look at this photo. https://dieselcranks.com/iveco-case-nef-445t-m2-engine-complete-core-esn-683919-16-bcn-4896382.html

Every other diesel I've worked on had the pump in the front, like you said, to run off the timing gears, but it seems that this one has the pump mounted towards the rear of the engine. Hopefully this week I can run the flow tests!

NH575E, thanks for the input. I hope to be able to go through all of the lines soon. Of course, I have to do this during the winter... At least it is inside!

 

[NH575E]

This should be the parts listings for your tractor if it helps.
https://partstore.construction.newholland.com/us/NashvilleTractorInc/parts-search.html#epc::mr61342

This diagram shows the pump facing forward. (note the arrow at the bottom right indicates direction)
https://partstore.construction.newh...ctorInc/parts-search.html#epc::mr61342ar20379

Siphon some fuel off the bottom or look in the tank to see if it has any rust to start with. Pull the hose at the #12 elbow in this illustration and blow into the hose with the cap off the tank. That will check the main supply line. Check that elbow and follow the lines from there checking for any potential restrictions.
https://partstore.construction.newh...torInc/parts-search.html#epc::mr61342ar518205

Note: On any of the parts illustrations you can click on the "Print Assembly" button and it will prepare a PDF copy for you to download. These are very handy for service and parts identification. I will often copy the part number and search for it on ebay to see if I can find any NOS listings.

 

[thepumpguysc]

I couldn't get the last 2 links to come up.??
If yours looks like the link YOU posted..the lift pump is behind the inj. pump & the shut off sol. is ON the inj, pump behind the steel lines.
The lift pumps are a weak spot in the system..
While holding the throttle WIDE OPEN..
Just loosen the line coming out of the lift pump going towards the inj. pump & crank the engine.. Fuel should spurt out.. Tighten it up & keep moving closer to the inj. pump.. checking the flow along the way..
Once u determine fuel is getting TO the inj. pump inlet.. Check the shut off solenoid.. & once u determine THATS WORKING.. Loosen ALL the lines up AT THE INJECTORS.. & crank the engine.. Wait until u get fuel spurting out of there & tighten the lines.. work the grid heater & it should start..
Good luck.

 

[Delmer]

You know you had water and sludge in the fuel system. And a progressively worsening problem. I don't think you're going to get fuel spurting from the lift pump. If you do, then follow thepumpguy's procedure.

To judge the transfer pump by the feel of the manual priming lever, you have to understand how the pump works. It DOES NOT pump up so the lever gets stiff, it operates just like the cam does, the cam would over pressure the system in a second if it pumped up and got stiff.

When you move the lever, you're pulling the diaphragm down sucking fuel into the pump chamber, let it go and an internal spring applies pressure to the diaphragm and fuel. If the fuel flows out then you'll suck fuel with the next stroke. If the fuel holds the pressure and doesn't go anywhere, the diaphragm won't push up and won't add any spring pressure resisting the next stroke of the lever, you'll only feel the tiny external return spring on the lever. The lever will only be hard to pump if there is a blockage of the suction side of the transfer pump, you'll be pulling against the vacuum and the spring at the same time.

This assumes the pump is working and is like every one I have run into. Easy enough to test by running temporary hoses and blocking them with your finger. Or use a vacuum/pressure gauge teed into the suspect lines.

Where are you in WI?

 

[DoubleK]

This should be the parts listings for your tractor if it helps.
https://partstore.construction.newholland.com/us/NashvilleTractorInc/parts-search.html#epc::mr61342

This diagram shows the pump facing forward. (note the arrow at the bottom right indicates direction)
https://partstore.construction.newh...ctorInc/parts-search.html#epc::mr61342ar20379

Siphon some fuel off the bottom or look in the tank to see if it has any rust to start with. Pull the hose at the #12 elbow in this illustration and blow into the hose with the cap off the tank. That will check the main supply line. Check that elbow and follow the lines from there checking for any potential restrictions.
https://partstore.construction.newh...torInc/parts-search.html#epc::mr61342ar518205

Note: On any of the parts illustrations you can click on the "Print Assembly" button and it will prepare a PDF copy for you to download. These are very handy for service and parts identification. I will often copy the part number and search for it on ebay to see if I can find any NOS listings.

I looked at the diagrams you posted and thought 'they don't look like my injector pump or motor'. So off I went to the local NH dealer to talk to the parts dpmt. I told them what my problem was and how I wanted to check the voltage on the shutoff at the inj. pump, but thought it was in the back, yet others sent diagrams of it in the front. He said that it's a Cummins motor and the earlier series was in the front, but the newer ones are in the back. He then looked up my serial number and the diagrams showed the pump in the back, right next to and behind the fuel filter. He said that if the filter housing doesn't have a plastic cylindrical looking thing on top, then it's a mechanical lift pump located right below the filter, which is what mine is; mechanical. He was surprised to learn that there is only one fuel filter and that it is the water separator as well.

So, off to check the fuel lines and lift pump...


Delmer, I am in the Fox Valley area. You?

 

[Delmer]

I'm more or less near LaCrosse, but I get around the state a bit, more central WI than the Fox Valley though.
I'm sticking with 9 out of 10 you have a problem before the injection pump. I don't think a solenoid would fail gradually like that.

 

[thepumpguysc]

U have an engine infront of u.. You've been sent several diagrams & u cant figure out where the lift pump is, & you cant find the shut-off solenoid..
& cant figure out, if or how u have fuel to either of the pumps.. ALL BECAUSE everything is "backwards"..?

 

[DoubleK]

U have an engine infront of u.. You've been sent several diagrams & u cant figure out where the lift pump is, & you cant find the shut-off solenoid..
& cant figure out, if or how u have fuel to either of the pumps.. ALL BECAUSE everything is "backwards"..?

Not exactly sure I understand what you're saying. I described the location of my injector pump and was trying to understand whether this system had two lift pumps and two filters. Googling and ebay provides a listing for both electric and mechanical lift pumps for the LB's. I was also trying to locate the fuel shutoff to verify that I had 12V there, as I had found evidence that some mice had started feasting on my wiring near the fuse panel. Then, I was told that my injector pump was NOT located in the back of the engine, but in the front and diagrams were provided that showed a year range that included my machine. The diagram showed an injector pump with the gear end facing the front of the engine. HOWEVER, it did not look at all like my injector pump AND my pump is located in the rear of the machine. At this point I decided to question the parts guy at the local NH dealer to make sure of what I was seeing versus what the diagram showed. He CONFIRMED that my series was different from those in the other diagram, and was located on the rear of the engine.

So, can I figure out where the lift pump is? Yes, as I stated before, mine is mechanical and I tried to manually pump it. I had asked whether or not these pumps go out, since they remind me of the fuel pumps from the '70s and '80s from Ford. I also asked if there were two, on one system, one electric and one mechanical, since a listing is provided for both. I also asked for the location of the shutoff solenoid since mine is different from the ones in the diagram. Also the service manual on cd that I have for this tractor does a great job describing the components of the tractor from hydraulics to axles, BUT nothing on the fuel system or the engine. Reading about the shutoff's, the location has been mentioned as to be 'on the top'. Well, my pump has no such animal. In fact, there are two electrical components on my pump. The one located on the front side of the pump is the shutoff. The one located on the side is the electronic timing control.

I guess it would depend upon your definition of backwards. According to what I had posted earlier, I knew what I was looking at, but it was backwards to those trying to help.

 

[Tinkerer]

What was the result of your effort to operate the mechanical pump manually ? It cannot be manipulated unless the pump arm is off the cam lobe entirely. Usually that has been my experience.
I believe you are going to have to find the service manual for the engine. It is not unusual for a tractor service manual to without the fuel system manual.
Take a look on page #33 here --->https://docs.google.com/file/d/0BxL4Vd2OEMoIUGY2R2x0RWtXR0E/edit
I just took a quick look at it. There is much more in the manual. I think !

 

[NH575E]

I looked at the diagrams you posted and thought 'they don't look like my injector pump or motor'. So off I went to the local NH dealer to talk to the parts dpmt. I told them what my problem was and how I wanted to check the voltage on the shutoff at the inj. pump, but thought it was in the back, yet others sent diagrams of it in the front. He said that it's a Cummins motor and the earlier series was in the front, but the newer ones are in the back. He then looked up my serial number and the diagrams showed the pump in the back, right next to and behind the fuel filter. He said that if the filter housing doesn't have a plastic cylindrical looking thing on top, then it's a mechanical lift pump located right below the filter, which is what mine is; mechanical. He was surprised to learn that there is only one fuel filter and that it is the water separator as well.

Try this link for your tractor then.
https://partstore.agriculture.newho...orEquipmentInc/parts-search.html#epc::mr53712

Looking at the fuel system links at the bottom of the engine section for the NA version tractor looks like the components you are describing.

 

[DoubleK]

What was the result of your effort to operate the mechanical pump manually ? It cannot be manipulated unless the pump arm is off the cam lobe entirely. Usually that has been my experience.
I believe you are going to have to find the service manual for the engine. It is not unusual for a tractor service manual to without the fuel system manual.
Take a look on page #33 here --->https://docs.google.com/file/d/0BxL4Vd2OEMoIUGY2R2x0RWtXR0E/edit
I just took a quick look at it. There is much more in the manual. I think !

Tinkerer, At the time I tried to manually prime it, I didn't notice anything happening. The shop did confirm what you just said, if the cam is in the wrong position, you can pump until your finger is noticeably shorter, but it will do no good!
Thank you for the link to the fuel system. It does seem that there is only one fuel filter...

Try this link for your tractor then.
https://partstore.agriculture.newho...orEquipmentInc/parts-search.html#epc::mr53712

Looking at the fuel system links at the bottom of the engine section for the NA version tractor looks like the components you are describing.

NH575E, good job on locating the manual. I did go through it for the fuel system. I'll save the link for further use. Again, good job and thanks.

 

[NH575E]

NH575E, good job on locating the manual. I did go through it for the fuel system. I'll save the link for further use. Again, good job and thanks.

Don't forget you can click on the "Print Assembly" button and download those pages in PDF. You never know when a company may decide to take something off line.

 

[DoubleK]

Bad manual fuel pump. Replaced, and is running.

 

[thepumpguysc]

Thanks for letting us know.. GOOD THING it was just a supply pump!!!
The inj. pumps for those NH aren't cheap..
Just a friendly tip>> at the FIRST SIGN of any power lose, change the filters right away.. & its best to have a maint. schedule inplace for that machine.. or change the fuel filters 2x a year {minimum}.. THAT MACHINE needs "special" attention.. Happy Tractoring..

 

[DoubleK]

Thanks for letting us know.. GOOD THING it was just a supply pump!!!
The inj. pumps for those NH aren't cheap..
Just a friendly tip>> at the FIRST SIGN of any power lose, change the filters right away.. & its best to have a maint. schedule inplace for that machine.. or change the fuel filters 2x a year {minimum}.. THAT MACHINE needs "special" attention.. Happy Tractoring..

Thank you for the tip. I will pick up a few filters to have some on hand.
It was good to work it for awhile! (even tho it was only 20 degrees out.)