Loss Of Power

[OSIAS]

Tractor L2501 HST
Front Loader LA525
Backhoe BK976
Brushog as wide as my rear tires

I am no tractor or engine expert by any means please don't act like I am ( I am a noob but a jack of all trades ). I do a mix of my own maintenance and from time to time take it into the shop. This has been occurring since after a full yr or two of owning it ( Think I have owned it close to 4 yrs now ).

Pretty straight forward issue loss of power, feels like I have a clogged air filter or just hit some bad gas. The RPM Lever is at max and I understand pulling my foot off the gas to let it recover or finding that right balance to let the machine move and eat and maintain the RPM's it needs.

I could be driving on a flat surface and randomly I can't give it any gas or its will basically die. Eventually it works it way out, I have no idea why. When this happens while under load or on an angle and under load its a real nightmare. Even if it dies I can start it right back up without any load and it will go right back to the high RPM Idle but soon as I put my foot on the gas it will chug the RPM's down fast and will die. I could move a foot wait 5 secs for the idle to rev up move a foot rinse and repeat till whatever is wrong works its way out. Then its fine again for who knows how long, 5 mins or 5 hours but it will happen again.

1. I can do all the regular maintenance on it but I can't tell that it does anything.
2. I have replaced or cleaned the air and gas filter multiple times.
3. I have replaced all the oil and hydraulic fluids and filters, there was a little metal flake on the magnet but I don't think it was a lot.
4. I put Heat ISO thinking maybe some water condensation built up in the tank - no change
5. I pulled and checked all the gas lines from the tank to the engine. They don't have any leaks or holes that I can tell and the gas looked okay and being pumped all the way.
6. I am not loosing any fluids anywhere

I am hoping people can provide some logical direction on what I should do and why. I will then put some time aside to do them to hopefully remediate this.

Thank You in advance for your efforts

 

[GreensvilleJay]

possibly crap in the gas tank that wedges in the outlet spigot of the tank.

had that with my BX23S.3 YEARS ago.semifloating 'sliver' of plastic finally wedged into the spigot. $2 filter on the tank inlet and 600+ hrs later NO more problems !

 

[D2Cat]

Well, hopefully you're not using gas but you keep referencing the fuel as gas. Make sure you have clean fresh diesel in the tank, but your description indicates a fuel restriction some place. As mentioned, probably some obstruction in the tank and when more fuel is needed for a heavy load it's not able to flow and the engine chokes down.

 

[JimmyJazz]

The next time you experience this problem disconnect the fuel line at the filter and blow the fuel back into the tank and see if that might clear an obstruction. There is also probably a small inexpensive diaphragm type fuel pump that may have gone bad that I would replace if clearing the line with air doesn't help sort the issue. Good luck.

 

[OSIAS]

Wait its diesel? Kidding..

Based on what I am hearing this actually makes a lot of sense just dumping the tank may not solve the issue entirely either as crap could get back in the tank. ( even though its expensive with todays prices I will dump it just to make sure fresh fuel )

Let me tackle this next unless anyone has other ideas or objections.

I will dump the tank and include a filter on the exit that would make it impossible for odds and ends to block.

Then it will be a test of time to figure out if this is the issue. Maybe when I dump the tank it will become apparent this is the issue as well if there is a bunch of crap in the bottom.

I Will update when I can get the parts and time to do. Again unless anyone else has other concerns

 

[GreensvilleJay]

Honestly, I'd dump the tank( SAVE the fuel !!!), then inspect the inside of the tank.
If you have a 'floater' you may NOT get it out by 'draining'.
I had to remove the tank from my BX23S, toss water in, get it upside down,slosh it around, drain SEVERAL times before the 'sliver or chard' of plastic came out. I then filled the tank with water, allowed to gravity drain, blow dry, WW fluid slosh, blowdry, sit in hot sun for 1 hr,inspect, THEN reinstall.
Yes, a lot of steps, probably more than needed but after 3 years, 600hrs NO problems.

hrs on machine ?? maybe diesel has got algae or other semi floating crud in it, though usually it'll show in filter as black krap.... a sliver that mechanically blocks the spigot, you'll never see unless you look inside the tank.

 

[85Hokie]

The next time you experience this problem disconnect the fuel line at the filter and blow the fuel back into the tank and see if that potentially clears an obstruction. There is also probably a small inexpensive diaphragm type fuel pump that may have gone bad that I would replace if clearing the line with air doesn't help sort the issue. Good luck.

WHEN you do this............ verrrrrrrry little air psi is needed ............. like 5 maybe 10 psi. Otherwise you'll have more problems than you wish

 

[RCW]

There’s a lot of instances where folks have similar symptoms with an L series.

Many times, it turns out to be a problem with the water separator/fuel filter housing.

They’re often not reinstalled correctly, have a clog in the 90-degree fitting entering the housing, or miss an o-ring.

Before I pulled or dumped fuel tanks, I’d start here.

I don’t have the same setup, but I’ve seen them give a lot of guys heartburn here on OTT..

Always start with the simple stuff.

 

[D2Cat]

WHEN you do this............ verrrrrrrry little air psi is needed ............. like 5 maybe 10 psi. Otherwise you'll have more problems than you wish

Also, if you blow back towards (into) the fuel tank remove the tank cap.

 

[OSIAS]

Was going to say, does anyone have an easy tear down to get the gas tank out of my L-Series HST Tractor?

I can't find any vids on it, the manual isn't very clear on it, seems much easier to pull off on other models, not so much on mine. I want to ensure nothing in there but I am uncertain the best way how..

@RCW I am all about an easy common sense fix, got a particular link or steps to follow? I replace the filter regularly, I see no issue with fuel flow. But if there is something specific I could do or test and or replicate?

I would imagine if there are that big of a issue there should be a troubleshooting sticky somewhere I am looking.

 

[OSIAS]

Having the fuel tank pulled off seems tricky. I have drained it let it sit for days, took a vacuum to the inside of the tank repeatedly to suck up anything loose in it. I would find it hard to imagine some debri large enough to clog the intake is left.

I have pulled the fuel filter unit completely off and cleaned it, it was dirty as hell even though I did just replace the filter recently.

I have a glass of the diesel sitting in a cool dark place going to let it sit a day or so and see if there is any separation.

& go from there

 

[OSIAS]

Okay the diesel in the glass is fine no separation at all. There was some gunk in my fuel filter so I did order some biocide to put into each can but that has not arrived yet and I can't imagine that is the real full issue. I filtered all the diesel I put back into the tank. There should not be anything in the tank or in the lines or fuel filter causing the issue.

After completing the work in the previous post I fired it back up and took it for a spin. First 10 mins seemed good and strong. With brush hog on was eating big stuff moving with power no issue.

Once I accidently hit a stump not ground down far enough under some dense brush causing it to chug a bit it was game over. Once it chugged and lost power the one time it never recovered. From then on out everything was just too much and I was constantly loosing power again just as before and I was having to nurse / baby it. Even small stuff or just going up hill loss of power.

What should I look at next and why? This is annoying for sure.

 

[Nicksacco]

Based on your description of hitting the stump and such, I wonder if the problem is not with the tractor, but something bent or broken at the PTO or after.
If so, it could be lugging the tractor's engine down.

 

[OSIAS]

Best I can tell the PTO is A-OK, doesn't mean I know what I am looking for though. Do you have a mishap checklist or something I can run down or a way to rule things out?

To me it doesn't matter the implement, I can put on my box scraper with no PTO usage and still have loss of power problems.

 

[OSIAS]

Yesterday I called my local shop that I have taken this into a couple times. I walked them through what I have done and why and asked there recommendation. Basically they recommend what I have done.

They think its a fuel issue as well and want to hook a computer up to it, I believe once thing he mentioned was to test the injection pump or the timing could be off. Which will cost me probably 750 just to get it into the shop and back much less any work they do.

I am thinking about replacing all my fuel lines or hoping there is something else I could do.

I then come across this..

If this is the issue or something similar I think this I think is above my capabilities and I would prefer putting it into the shop. Unless someone can really simplify how to test this and timing etc. I have never messed with timing or injection on any engine.

 

[D2Cat]

I think the guy in the video is hoping and dreaming.

Osias, you say your machine ran fine after cleaning the fuel, then when you hit something hard while mowing and dropped the RPM the engine began stumbling and never picked up RPM again. That tells me the engine bogging down has nothing to do with the timing. Simply because the engine runs fine for a while, and timing is only changed by changing the thickness of shims under the IP. I think perhaps the impact of the stump broke some more gunk (algae) loose in your fuel system.

 

[OSIAS]

Then you think biocide will solve my problem, or your recommending what?

Biocide arrives Monday, plan on finding out..

 

[OSIAS]

I am past algae being the issue. Use it as a measure of something you can now rule out, nothing is in my tank either. I debated started a new forum thread so one would approach it with the fresh mindset. I think I have a overheating issue and here is why as I have done a fair amount of testing.

Basically from a cold start after its been sitting - it will run like a beast for 15-20 mins under MAX load then it starts to bog. Doesn't matter what load I put it under its BEASTMODE. At 15-20 it heats up, the gauge gets about 1/3 of the way up then power loss begins. Power loss is slight and as it gets hotter it gets worse. The gauge is not even halfway or even in the red, so I would not think this is the issue. But being that the only thing I can tie the loss of power too is a heat and time from start each time. Many tests to confirm.

Not to say that perhaps some algae wasn't in my system or the filter didn't need to be cleaned and didn't play a part etc, but its not the main culprit and I still have a power loss problem and these are not it. I can promise without fail from cold start for the first 15-20 Mins I will have MAX POWER every time.

So today I did full radiator maintenance cleaning & flush. Screen wasn't bad but and the radiator fluid was pretty good still, I did this last winter. However the radiator fins absolutely did need cleaning.

Next outing I was able to run BEASTMODE for probably about 30-35 mins before it reaches 1/3 up on the heat gauge and just starts loosing power again.

So I haven't don't much research on the next bit yet. How to I test my cooling system, is there an easy way. Does it have a pump etc.

Anyone have advice I will listen.

 

[PoTreeBoy]

I am past algae being the issue. Use it as a measure of something you can now rule out, nothing is in my tank either. I debated started a new forum thread so one would approach it with the fresh mindset. I think I have a overheating issue and here is why as I have done a fair amount of testing.

Basically from a cold start after its been sitting - it will run like a beast for 15-20 mins under MAX load then it starts to bog. Doesn't matter what load I put it under its BEASTMODE. At 15-20 it heats up, the gauge gets about 1/3 of the way up then power loss begins. Power loss is slight and as it gets hotter it gets worse. The gauge is not even halfway or even in the red, so I would not think this is the issue. But being that the only thing I can tie the loss of power too is a heat and time from start each time. Many tests to confirm.

Not to say that perhaps some algae wasn't in my system or the filter didn't need to be cleaned and didn't play a part etc, but its not the main culprit and I still have a power loss problem and these are not it. I can promise without fail from cold start for the first 15-20 Mins I will have MAX POWER every time.

So today I did full radiator maintenance cleaning & flush. Screen wasn't bad but and the radiator fluid was pretty good still, I did this last winter. However the radiator fins absolutely did need cleaning.

Next outing I was able to run BEASTMODE for probably about 30-35 mins before it reaches 1/3 up on the heat gauge and just starts loosing power again.

So I haven't don't much research on the next bit yet. How to I test my cooling system, is there an easy way. Does it have a pump etc.

Anyone have advice I will listen.

How many hours on this tractor? Some folks are going to tell you to take temperature readings on the top and bottom radiator hoses with an infrared (non-contact) thermometer and report back.

BTW (I haven't read the back posts), have you loosened the fuel cap while doing this warm-up to make sure the cap vent isn't plugged up?

 

[Henro]

Is there ANY CHANCE the fuel cap vent is blocked and causing a vacuum in the tank as you consume fuel? Thereby cutting off fuel delivery after a period of use?

Just a WAG…run the tractor with the fuel cap loose and see if it makes a difference. Stranger things have happened.