2019 L2501 engine fuel system issues after engine warms up?

[pete.rocha1970]

Hi, new to the forum, and i am hitting my head trying to figure this out. I have been looking at posts with similar problems but i'm at a loss on next steps.

So on my L2501, I can start it just fine, and drive it at full throttle for a while, but then it would start belching black smoke and start running rough and eventually die.

So I have:

1. Checked to make sure fuel line from tank is clear of obstructions.
2. Make sure fuel cap is venting.
3. Replace fuel filter and air filters and bled system.
4. Checked fuel lift pump (didn't seem to have issues), but replaced it anyway.
5. Checked fuel shutoff soleniod, replaced it anyway.

so after doing #5, what i started noticing is:

A. I can run it at idle and it seems to run fine for at least an hour.
B. I can run it at 1/2 throttle and seemed to be fine too.
C. BUT when I run it at full throttle, it will get up to rpm, and it will run fine for about 10 minutes until the engine gets up to temp, then it starts with the black smoke and drop in RPMS. I will usually stay running, but poorly.

At this point I was thinking maybe I was having an electrical problem, maybe in the soleniod relay or the timer circuit, so I just pulled the fuel shutoff solenoid completely (killing engine by crimping fuel line) and it still does the same thing.

So now i'm to it has to be a non-electrical issue somewhere in the injection pump, but the amount of time it takes to happen has me head scratching.

Anyone with any ideas I would appreciate it.

 

[Russell King]

Black smoke indicates that it is over fueling (not restricted flow) or more precisely that all the fuel in the cylinder is not burning before being exhausted. See the chart (move down a bit) about smoke and causes for the different sources of smoke colors.

The Causes of Diesel Blue Smoke And What To Do Next - learn diesels

So, you have some blue smoke billowing out of your exhaust. Well, you think it’s blue. Does it look like […]

learndiesels.com

You need to figure out where the excess fuel is coming from.

Start by checking the engine oil level to see if it is high. The hydraulic pump may be able to pump hydraulic fluid into the crankcase when the shaft seal fails. Also some mechanical lift pumps will pump fuel into the engine crankcase if the diaphragm fails. (You replaced yours but the crankcase may have been over full)

I suspect the over full crankcase because of the RPM being higher when the smoke starts. The crankshaft is throwing oil everywhere and can cause mist that can get into the cylinders. If the oil is over full then it is just worse than normal since more foam and mist is being created.

If that is not the problem then look at having the injectors rebuilt or replaced with new or rebuilt injectors. (Just don’t buy them from the general internet- go to dealer or a reputable rebuild shop.)

You may have a problem with the injector pump also putting too much fuel in the engine. It can be tested and if needed rebuilt.

Good luck and let us know what you find out and you will get more suggestions from other more experienced people if you keep the thread active.

 

[pete.rocha1970]

Black smoke indicates that it is over fueling (not restricted flow) or more precisely that all the fuel in the cylinder is not burning before being exhausted. See the chart (move down a bit) about smoke and causes for the different sources of smoke colors.

The Causes of Diesel Blue Smoke And What To Do Next - learn diesels

So, you have some blue smoke billowing out of your exhaust. Well, you think it’s blue. Does it look like […]

learndiesels.com

You need to figure out where the excess fuel is coming from.

Start by checking the engine oil level to see if it is high. The hydraulic pump may be able to pump hydraulic fluid into the crankcase when the shaft seal fails. Also some mechanical lift pumps will pump fuel into the engine crankcase if the diaphragm fails. (You replaced yours but the crankcase may have been over full)

I suspect the over full crankcase because of the RPM being higher when the smoke starts. The crankshaft is throwing oil everywhere and can cause mist that can get into the cylinders. If the oil is over full then it is just worse than normal since more foam and mist is being created.

If that is not the problem then look at having the injectors rebuilt or replaced with new or rebuilt injectors. (Just don’t buy them from the general internet- go to dealer or a reputable rebuild shop.)

You may have a problem with the injector pump also putting too much fuel in the engine. It can be tested and if needed rebuilt.

Good luck and let us know what you find out and you will get more suggestions from other more experienced people if you keep the thread active.

Thanks you, I will check that out and report back. I only get to work on it on weekends. And I understand all of what you said, but its the amount of time it takes that is odd. I'd kind of expect that it should start showing that right away and not after 10-15 minutes of running, but i'll check and respond to what i see.

kind of stinks since the tractor only has 200 hours on it

 

[North Idaho Wolfman]

Have you looked at the Air Cleaner.

 

[Russell King]

Well that’s a good idea that didn’t even cross my mind

 

[North Idaho Wolfman]

Well that’s a good idea that didn’t even cross my mind

Seen quite a few with plugged up air boxes and dirty filters cause all sorts of issues that mimic overfueling.

 

[North Idaho Wolfman]

Typically Injection pumps can not "overfuel", they can underfuel.
If the injectors are bad they tend to overfuel when they are cold and underfuel when they are hot.

Have you ever used starting fluid on it?

 

[pete.rocha1970]

Have you looked at the Air Cleaner.

Yes, as noted in my original post, first things i did was put in brand new fuel and air cleaners

 

[pete.rocha1970]

Typically Injection pumps can not "overfuel", they can underfuel.
If the injectors are bad they tend to overfuel when they are cold and underfuel when they are hot.

Have you ever used starting fluid on it?

No, I haven't. Never had to, it always started up just fine even when its very cold outside.

 

[pete.rocha1970]

Seen quite a few with plugged up air boxes and dirty filters cause all sorts of issues that mimic overfueling.

Thats what my first though was and was the first things I did when it started acting up.

 

[pete.rocha1970]

Thanks you, I will check that out and report back. I only get to work on it on weekends. And I understand all of what you said, but its the amount of time it takes that is odd. I'd kind of expect that it should start showing that right away and not after 10-15 minutes of running, but i'll check and respond to what i see.

kind of stinks since the tractor only has 200 hours on it

Actually as a note, i did finally see another thread where a person noted the same thing, and a person posting did note the delay time could be due to the time it took the oil to get hot and get thin enough to bypass the rings when the oil was too high. It was time for an oil change in it anyway, so going to do that next and cross fingers.

 

[BAP]

Yes, as noted in my original post, first things i did was put in brand new fuel and air cleaners

Yes, but have you checked the hose between the air cleaner canister and the intake manifold? Get your tractor running until it starts smoking, pop open the hood with it still smoking and see if the hose is still round or collapsed. I have seen hoses collapse after running a while causing the exact same symptoms you are experiencing.

 

[Trash Panda]

Yes, but have you checked the hose between the air cleaner canister and the intake manifold? Get your tractor running until it starts smoking, pop open the hood with it still smoking and see if the hose is still round or collapsed. I have seen hoses collapse after running a while causing the exact same symptoms you are experiencing.

That is something that I would never have guessed to be an issue.

Good call.

 

[BAP]

That is something that I would never have guessed to be an issue.

Good call.

Usually it is on an engine that is several years old and the rubber in the hose has started to deteriorate and lose its strength to hold shape under load.

 

[Trash Panda]

Usually it is on an engine that is several years old and the rubber in the hose has started to deteriorate and lose its strength to hold shape under load.

Soft rubber on a hose that sees vacuum seems like a poor choice.

 

[pete.rocha1970]

Yes, but have you checked the hose between the air cleaner canister and the intake manifold? Get your tractor running until it starts smoking, pop open the hood with it still smoking and see if the hose is still round or collapsed. I have seen hoses collapse after running a while causing the exact same symptoms you are experiencing.

I just was able to last night. I actually ran it with the hood open and watched and felt and the air hoses were fine.


Thanks for the tip though.

 

[pete.rocha1970]

Well that’s a good idea that didn’t even cross my mind

Russell, just as an update, (unfortunately i was in a hurry so i didn't check the oil level before I started the engine after it set for a week), but I started the engine, and ran it at full throttle. It actually took a lot longer than before for the problem to rear its head, but it did. The smoke was grey..like a blue grey and instantly my wife and i could smell it was NOT just burning diesel.

The "interesting" part is that when it started, it did not effect the engine quite to the degree it was doing before. I mean don't get me wrong its horrible, but the engine stays running above 2k rpm.

after stopping the engine and trying to let it set for a bit to get some oil drain back into the pan, i checked, and the oil isn't massively above the full mark, but it is. What the oil is, is the most dirty black i've seen with the consistency of almost diesel itself..maybe a tad thicker. So maybe i did have a leak in my lift pump that had filled the case, but after replacing it, the engine has been burning some volume off and isn't being effected quite as bad...but that is just wild conjecture on my limited knowledge of things at this point.

Anyway, i'm going back up to it tonight and will do a full oil and filter change, and see if it behaves itself. If it does i'll keep a close eye on things to make sure maybe i don't have a seal issue in the injection pump. If it doesn't cure the problem i'll report back. Thanks again for the pointers.

 

[Russell King]

Thank you for the update!

When you drain the oil, put some into a glass jar (so you can see it). If it is diesel fuel you should be able to smell it in the oil (I think). But put a lid on the jar and put it on a shelf to see what happens after some time - a week or two. I think diesel would separate out from oil but no idea if the hydraulic oil would separate out from motor oil.

You could send it out for some analysis if you desire to. Here is one place to consider

Oil Analysis | Blackstone Laboratories

Learn what's going on in your engine with oil analysis. Our free kits are easy to use and we explain the results in plain English! Since 1985.

www.blackstone-labs.com

 

[Runs With Scissors]

I would send the oil out as well.

If for no other reason than to simply “cross it off” the list.

Cheap “peace of mind”.

 

[pete.rocha1970]

Thank you for the update!

When you drain the oil, put some into a glass jar (so you can see it). If it is diesel fuel you should be able to smell it in the oil (I think). But put a lid on the jar and put it on a shelf to see what happens after some time - a week or two. I think diesel would separate out from oil but no idea if the hydraulic oil would separate out from motor oil.

You could send it out for some analysis if you desire to. Here is one place to consider

Oil Analysis | Blackstone Laboratories

Learn what's going on in your engine with oil analysis. Our free kits are easy to use and we explain the results in plain English! Since 1985.

www.blackstone-labs.com

Thanks. I still have the old oil. Unfortunately, changing the oil didn't help. I even underfilled it a tad. Still the same issue. Runs fine until it gets hot then starts burning oil from crankcase i'm assuming. Next steps? Do leak down tests on the cylinders? I'm really wanting to try to avoid taking it to the dealer lol.