5 Problems with John Deere 5125R (Explained)

John Deere 5125r Problems

John Deere 5125R are considered reliable tractors as they are simple with fewer parts that hardly fail. However, you can still run into issues with these tractors. We have met some complaints among users both online and face to face.

The most common complaint among users is ‘my John Deere 5125R engine won’t start!’ This is because most of the problems you will face with these tractors may end up affecting the engine. 

We are going to look at various problems that may potentially interfere with your John Deere 5125R tractor operation and how to solve them. 

Why is my John Deere 5125R Diesel Engine Not Starting?

There are several potential reasons why your 5125R engine tractor may fail. However, we are only going to address the most commonly encountered issues including:

  • Clogged fuel filter or fuel line
  • A dead battery
  • Overheated engine
  • Air in the fuel line
  • Stuck injection pump

1. Clogged Fuel Filter or Fuel Line

The filter is one of the first areas to inspect when your diesel engine can’t start. When the filter gets dirty, it clogs the vent thereby hindering the fuel from traveling from the tank to the engine.

To solve this, simply remove your fuel filter and examine it for dirt. If it is dirty, you will have to thoroughly clean it. However, it may be fully clogged to clean and may require replacement.

If the fuel filter is not the problem, you can check the fuel line. Fuel lines can cause the same problem as clogged filters. If the fuel line is dirty, you will have to clean it as well. 

2. A Dead John Deere 5125R Battery

If your tractor won’t start, you will be right to suspect a dead battery. Sometimes when the battery is dead, you may hear a click when you try to start your tractor. But this may not be the case all the time. Even when you don’t hear the click, the battery can still be a problem.

If you suspect a problem with the battery, you can start by cleaning the posts. When removing the terminals, start with the negative (-) then the positive (+). Ensure you thoroughly clean the terminals with something abrasive such as a mixture of water and baking powder.

When reattaching the cables after cleaning, ensure you reattach the positive first then the negative.

If cleaning the posts doesn’t work, it may mean your battery is completely dead. Some of the signs that may signify the end of your battery include swelling or bloating of your battery case.

You can also take it to a mechanic to help you test whether it has reached its lifespan. Most mechanics will carry out this test for free. If the battery is completely dead, then consider replacing it.

3. Overheating John Deere 5125R Engine

Part of your tractor engine may get overheated making your tractor not start. The simplest reason for overheating is the lack of coolant. Simply remove the radiator cap and examine your coolant level.

Be careful to wait until the engine cools before you remove the radiator cap.

Dirty radiator fins can also be a good reason for your tractor engine getting overheated. Dirty radiator fins won’t allow enough air to get into the engine and cool it.

To clean these, you can use an air compressor to blow dirt off the fin. Be sure to wait till the engine cools before you start blowing the specks of dirt.

If your water pump and cooling fan fail, they may cause your engine to overheat and prevent it from running. These problems are easy to correct and may cost you a little amount or nothing at all. 

4. Air in the John Deere 5125R Fuel Line

There has been a constant complaint of a case where a John Deere 5125R engine runs but misses.

When the engine runs but misses, there is likely air in the fuel system. If your tractor has air in the fuel line, the engine pressure will be interfered with and this will prevent the flow of the fuel to the engine.

Detecting air in the fuel line is simple. You will see bubbles in the fuel line. If that is the case, all you need to do is bleed the air out.

Bleeding air out of the fuel system is very simple. Simply open fuel-line unions, and carefully bleed ports downstream of the pump, one after the other starting with the one closest to the pump. Continue pumping until only fuel and no air runs out.

Once done, fix it back carefully, ensuring it doesn’t trap more air in the process. 

5. Stuck John Deere 5125R Fuel Injection Pump

A fuel injection pump is very important in the tractor’s diesel engine system. It is responsible for pumping fuel into the cylinder of the diesel engine. 

The pump won’t deliver fuel or may block the engine from accessing the airflow if it gets stuck either in a closed or an open position.

Fuel injection pumps are not easy to work on by yourself. I, therefore, recommend involving a professional mechanic if you encounter this problem.

It may cost you a lot in the long run if you attempt it by yourself than you would spend when you hire a professional.   

Is John Deere 5125R Reliable?

Generally, John Deere tractors are the most valued and sought-after tractors in the world. Despite being a newcomer, John Deere 5125R boasts a reputation that competes well with other tractors from this brand.

That is to say, it offers one of the highest reliability among John Deere tractors out there.

John Deere 5125R tractors have certainly raised their game with the transmission and features. Their cab layout and cab suspension are some of the features you will love with this model.

John Deere 5125R has plenty of horsepowers but doesn’t burn much fuel. So if fuel conservation is a priority to you, this is another factor you will love with this model. 

Do John Deere 5125R Tractors Come with a Warranty?

John Deere now offers a new extended warranty and protection plan on all new purchases of John Deere compact utility tractors including John Deere 5125R. Just contact your closest John Deere tractor dealer for more information. 

The warranty covers all parts of John Deere agricultural equipment except but not limited to modifying combined grain tanks; setting injection pump fuel delivery above John Deere specifications; modifying self-propelled sprayers with unapproved wheels, tanks, or booms.

Radios, tires, tubes, and batteries are warranted for the number of months or operating hours whichever occurs first. Meaning, these parts have different warranty durations. 


If you always encounter any of the above-mentioned problems with your John Deere 5125R tractor, we are glad you now have the solution.

If you can’t solve the problem even after going through this article, it is time you call a professional.

You can also contact us for more information because 5125R tractor issues are not limited to what we have addressed. Enjoy a smooth drive. 

Related Article: 3 Problems With John Deere 9200 Tractors (Explained)


John Deere – Warranty Service & Protection Plan

Utility Tractors | 5125R | John Deere US