I own a 1025R with the factory-installed H120 loader and 260 backhoe, currently showing 399 hours of use. After operating it for anywhere between one and five hours, the engine starts acting up — it begins sputtering, shaking, and emitting a light white smoke, often leading to a complete shutdown. Restarting the engine produces the same symptoms. From the driver’s seat, I can see that the fuel filter by the engine remains full, and the engine temperature reads as normal. If I leave the machine to cool down for an hour or more, it will start up again, sputter briefly, and then run smoothly.
To troubleshoot, I’ve already replaced both fuel filters and checked them for water or other unusual contaminants, but found none. I also replaced the air filter recently, so I doubt that’s contributing to the issue. Someone suggested a possible blown head gasket and advised me to check the radiator fluid level. While the radiator was slightly low, I’m unsure if that’s the problem since the machine runs fine again after cooling off.
I’m open to suggestions or ideas on what might be causing these issues. At this point, I’m reluctant to take it to the dealership, as it’s likely the tractor will work fine once there, leaving me with transportation costs and no solution.
Is the coolant clear and free of discoloration? Have you observed any black, foamy residue in it? Is the oil level where it should be? Did you only check the fuel filters and put them back, or were they replaced with new ones? Is the air filter mount secure, or could it be damaged or loose? A recall was issued for those a few years ago. Have you examined the fuel supply lines or injector rails to check for any potential leaks?
Is the coolant clear and free of discoloration? Have you observed any black, foamy residue in it? Is the oil level where it should be? Did you only check the fuel filters and put them back, or were they replaced with new ones? Is the air filter mount secure, or could it be damaged or loose? A recall was issued for those a few years ago. Have you examined the fuel supply lines or injector rails to check for any potential leaks?
You might want to take a moment to smell the white smoke you’re noticing—it could provide some clues. Typically, when a head gasket fails, the engine tends to push coolant out through the overflow or causes the recovery bottle to fill up due to the higher pressure in the combustion chamber compared to the cooling system. It could also be helpful to attach a fuel pressure gauge and observe what happens to the pressure when the issue occurs. There’s a chance the fuel pump could be weak as well.
Let us know what you discover — it could be valuable information for others dealing with a similar problem. One thing you might try is immediately reducing the throttle when the issue starts. If it’s related to a fuel shortage and the engine keeps running, that could give you a starting point.
When I replaced the inline fuel filter beneath the floorboard, I drained the fuel tank and didn’t notice anything that might obstruct the flow. However, it’s possible I overlooked something, so I plan to check it again. Regarding the fuel pump, I think I may have heard the ticking sound during its latest episode this afternoon, but I can’t say for certain.
The smoke smells strongly of diesel, as best as I can describe it. Years ago, I drove a Peterbilt with a Cummins engine, and I recall a similar smell when the turbo failed during a trip back to the office. The white smoke back then had the same distinct odor, though not as intense as what I’m experiencing now. If this 1025 had a turbo, I’d almost be convinced that’s the issue since the symptoms are remarkably similar. The only difference is that the Cummins wouldn’t restart until the turbo was replaced.
I plan to get a pressure gauge to monitor the system when the problem recurs. Once I figure out the cause, I’ll be sure to share what I find. Since I don’t get to run the machine daily, it might take some time to narrow it down.
Let’s take an optimistic angle and move away from the idea of a blown head gasket (with symptoms like sizzling oil or smoking coolant) to suggest a simpler explanation: fuel starvation or loss of prime. You’ve already checked both filters, so what about a possible issue with the lift pump? It could be a thermal malfunction causing the pump to fail when it heats up, or perhaps a connector losing continuity as the temperature rises.
I’m throwing in my two cents because of a similar experience. After a dealership left the lift pump unplugged (my conclusion, not theirs) while addressing a PTO indicator issue that wasn’t actually there (as mentioned in a previous post), my tractor exhibited the same symptoms—even with brand-new factory filters installed. A seasoned John Deere mechanic once told me these machines can sometimes start and run without a functioning lift pump, but under certain loads or positions, they may experience fuel starvation.
Here’s a suggestion: have someone test the Molex connector for the pump, bypass it if needed, or even try substituting a different impulse pump. They’re relatively inexpensive outside of dealer networks—I had to add one to my diesel Liberty. If the issue resolves after that, you’ve likely found the culprit. Good luck!
Earlier, I went to check on the tractor after it had been sitting overnight. When I turned the key, I could hear the fuel pump engaging, and the engine started up perfectly, running without any issues for about 10 minutes. Then it began acting up again. To rule out a clogged vent, I completely removed the fuel cap, but it made no difference. I also tried shaking the tractor to see if a potential blockage in the fuel tank might shift, but that didn’t help either.
When I installed the inline filter, I was careful to ensure the arrow was aligned correctly. Just to double-check, I crawled underneath and confirmed it’s positioned as it should be. I also inspected the air filter bracket in better light and couldn’t find any problems there.
Here’s something you could try: take off the radiator cap, start the engine, and look for any bubbles forming in the coolant. To get a clearer view, you may need to stop the water pump from spinning by loosening or removing the fan belt. Just be sure to monitor the temperature gauge closely to prevent the engine from overheating. It’s probably best to deal with the belt first, either by removing it entirely or disconnecting it from the crankshaft pulley.
If bubbles appear, it could indicate a head gasket issue or a cracked head. There are tools available, like a combustion gas detector, that can check for exhaust gases in the coolant, but I’ve never personally used one. Best of luck!
Sorry for leaving this unresolved for so long. To be honest, I just haven’t had the time to address it until now. I did go ahead and purchase the relocation kit for the air filter. I also checked with my local dealer about the warranty, and as expected, it has expired. I bought a new 2013 model in 2015, and the warranty ended in 2017.
Today, I replaced the air filter. As I mentioned earlier, the bracket itself wasn’t cracked, but the nuts securing it to the valve cover weren’t as tight as they should have been. They weren’t loose, but they could have been a bit tighter. After removing the bracket and cleaning off years of accumulated dust, I found a couple of hairline cracks in the valve cover near the front stud (see the photo below). For those familiar with the cracked cover issue, do you think this is enough to be causing the problem, or should I still be focusing on a fuel-related issue? Also, if this is the root cause, what are the chances that Deere would cover it even though the warranty has expired?
Looking closely at the photo, the marks on the surface appear to be scuff marks. The base of the unused bolt might raise some concerns, but that brings up a whole different issue. Typically, damage occurs when metal fragments from a broken cover get sucked into the engine’s valve train, leading to metal debris in the engine oil, which is never a good sign.
However, I don’t think the cover is the actual problem here. The rough running, stalling, and restarting that the original poster is describing seems unrelated to the air cleaner and cover. When an engine ingests metal from a damaged top cover, it doesn’t go back to running normally. Instead, the engine will struggle and eventually fail altogether after sucking in those metal fragments.
I still believe the issue lies within the fuel system. It could be an air leak or something similar in the fuel lines. You mentioned replacing the fuel filters, but I don’t recall if the fuel pump was replaced. The fact that the problem occurs once the engine is warm, but it runs fine after cooling down, suggests that the fuel system is still the source of the issue.
Be very cautious when working with the high-pressure fuel system on any diesel engine. Without the proper tools and experience, there’s very little you can do effectively, and the components in the system are precision parts that need to be carefully calibrated. Never attempt to clean injectors or fuel system parts with wire brushes or other harsh tools, as this will only cause further damage. It’s similar to trying to perform surgery on yourself — you don’t want to risk doing something that could make the problem worse.
If you’re unable to resolve the issue with basic repairs like fuel and filter changes, leave the more complex fuel system work to a professional. A trained technician with the right tools will be able to fix the problem properly, and in the long run, it will save you both time and money and get the machine running again.
I’m experiencing a similar issue with my 1025R, a 2019 model with 185 hours. The tank is clean, the filters are new, and the pump is functioning well. However, the filters were unusually dirty this time, even though I replace them annually. I suspect I may have received a bad batch of fuel. I typically use Howes fuel additive, but now I’m wondering if my injectors or glow plugs might be clogged.
I think I’ve found a solution to the problem, and it worked exceptionally well for me, with an added benefit.
Based on the feedback here, it seems the issue is related to the fuel delivery from the tank to the engine. The symptoms—smoking, shaking, knocking, power loss, inability to throttle up, and poor performance under load—were exactly what I was experiencing. Despite taking good care of my equipment, this issue had me stumped, but it turned out to be caused by bad fuel.
Here’s what I did:
- I checked my 55-gallon fuel barrel and confirmed that I had a contaminated batch of fuel.
- I drained the tractor’s fuel tank (it was only about a quarter full).
- I replaced both fuel filters, which were quite affordable.
- I added a can of diesel injector cleaner to the tank and filled it up with fresh diesel.
- Once the clean fuel and additive reached the engine through the filters, the smoking, shaking, knocking, and power loss persisted for a short time until the tractor started burning through the additive and fresh fuel. After about 15 minutes, all of the issues disappeared.
- I took the tractor out for a test run, using about a quarter tank of fuel, and put it under heavy load by moving wet mulch. It performed flawlessly, with no temperature issues or any of the previous symptoms.
- The bonus was that the injector cleaner really cleaned out the injectors. I noticed a significant improvement in speed and power, which means the bad fuel had really caused some clogging.
The product I used was LIQUI MOLY Diesel Purge (Made in Germany), which I picked up at NAPA. The 16-ounce can costs about $10. It can be used directly from the can or mixed with fuel.
My tractor now starts quickly and runs smoother with more power, like it’s brand new. I hadn’t realized how much it had slowed down over time, but the difference is remarkable. While it’s important to be careful about what you add to any engine, this product really worked for me.
