10 Most John Deere 4066R Problems & Troubleshooting

The John Deere 4066 is a superior compact utility tractor that can give you an upgrade in height and capacity. The powerful engine has 65 horsepower, which enables the machine to perform various farming tasks. You can rely on this tractor for seeding and everything that follows till you reach the harvesting phase.

But this doesn’t mean you have a perfect tractor. Some John Deere 4066r issues still make users unhappy with their machines. Most of these concerns are related to faults with the blades, bad steering, weak engine performance, or problems with the air ride seat.

This article will teach you everything there is to know about these issues with the John Deere 4066, whether you own one or are just interested in learning more about it.

The Most Common Problems with John Deere 4066R

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You can expect a versatile performance when you have a John Deere 4066R. But this does not mean it does not feature problems. However, these problems can be efficiently dealt with if diagnosed adequately. If you are unfamiliar with DIY tractor maintenance, you can talk to your local dealer for some guidance.

1. Poor Blade performance

A blade is essential for the work of any utility tractor. It enables you to level the ground or spread the seeds and soil, among other tasks. It is usual for blades to wear and tear with frequent use or due to accidental hitting. Luckily, the blade issue can be easily resolved with proper sharpening.

Sharpening a compact tractor’s blade on your own can be risky if you are not used to handling blades of this size. Bring the tractor to a nearby repair facility if you are unsure about your ability to manage this.

2. Noise coming from the transmission

The transmission or transaxle of your John Deere 4066r can sound a bit noisy, especially at the beginning of your machine’s use. This can be due to the teeth of the transmission gear, which could need a little wear to run more smoothly and quietly. This can happen in time, and the whining noise should decrease until it is gone.

However, if this issue persists, this should not be a problem with a new transmission gear. It can signify that the transmission fluid is experiencing an internal issue.

There could be a problem with the hydraulic fluid pump, limiting the amount of oil pumped to all transmission components. So, it would help if you looked for clogs in the pump or filter. Making sure these parts are clean can be a problem solver.

3. Lack of proper noise isolation

The engine of this particular John Deere model is known for being noisy. But this is not a very common issue with other tractors in the same category. It is probably a result of the extremely powerful turbocharged diesel Yanmar engine of the tractor, which provides up to 65 hp.

Luckily, this annoying problem won’t stick with you throughout the whole riding experience. It only lasts a few moments till the engine is done warming up. The turbo noise will remain, but it won’t be as annoying as before.

4. Battery charging problems

This is not something that is only categorized as one of the john deere 4066r problems. It is found in the John Deere 2305 tractor, as well. The battery of this powerful tractor can sometimes experience some issues. The most famous issue reported by many users is the difficulty of charging the battery.

A faulty part of the battery can cause this issue. Sometimes, corrosion can be extremely stubborn to clean and may require changing the terminal clamps.

However, sometimes the battery won’t charge due to improper tightness of the cables. In this case, all you should do is adequately tighten those cables. You could get a new battery if none of these attempts made things better.

5. Engine starting difficulty

Even a powerful engine like the one in the John Deere 4066R can experience starting problems. This is usually an issue with the fuel system. But before diving too deep into the system, you should ensure you are using fresh diesel fuel that did not go bad due to improper storage. Keep the fuel levels above the empty line to ensure the tractor’s proper running.

Also, you might need to check the fuel filter. It could be clogged and prevent fuel from going everywhere it should. In this case, you might want to try to clean it first. You can quickly get another one if this doesn’t unclog the filter.

Another member of the fuel system worth checking out, in this case, is the pump for the fuel injection. It could get defective with ongoing engine heat, so you might want to get another one.

6. Weak Air conditioner

Many users complain about the poor performance of the tractor’s air conditioner. The problem gets more annoying for residents of hot areas during the summer. The performance of the AC can’t be improved, but you should check to make sure that none of its parts are broken. 

So, if you suspect the performance is weaker than usual, you should check out the conditioner’s compressor. There could be an issue with the compressor, like it needs a recharge or some other sort of service.

A failing compressor will annoy you with unusual noise or decreased cooling efficiency. It can also emit cold air instead of hot air to alert you about the presence of a malfunction in the compressor.

So, with an inefficient built-in cooling system like the one in the John Deere 4066R, you might want to pay extra attention to the earliest failure signs. This helps to avoid a total breakdown of the already weak system.

7. No cracking in the starter

Another one of the widely reported John deere 4066r problems. This happens when the battery malfunctions for any reason. The starter will typically follow. The engine will not run whenever this happens, no matter how hard you try. Aside from a faulty battery, there could be a fluid leakage causing the starter to fail.

You can easily ensure the source of the starter issues, as the battery can be tested with a voltmeter. Also, fluid leakage can be detected easily by the starter’s smell and feel. Simply put, it will smell like diesel fuel or engine oil and feel wet. If it is a battery’s fault, you can replace both the battery and the starter.

Also, detecting the leakage source and treating it by replacing the starter can restore the engine’s running efficiency to normal. So, generally, you will need a replacement for the starter, as a flooded or damaged starter won’t be fixed.

8. Poor steering

This problem happens with Kubota MX5400 too. When you cannot steer the wheel as smoothly as before, you should suspect airlocks in the steering system. Air is not supposed to be present in the steering pump, as it prevents a smooth flow of the hydrostatic fluid into the steering system components. The only option in this situation is to bleed the air out.

9. The wheel wanders in a specific direction

This is another issue related to the steering system. You can notice this issue when you find the wheel heading in one of the directions (left or right). This can be a sign of a defective member of the power steering gear. This calls for opening the gear and inspecting components for occasional wear and tear. You need to replace the faulty part

10. Engine gets overheated

When the engine of your John Deere 4066r overheats, you can have various culprits to suspect. First of all, it could be an indication of a problem with the radiator. The solution could be as simple as filling the radiator with water, as its levels could drop with frequent use. You can add more water to meet the adequate levels.

Also, you can face this issue due to a faulty cap on the radiator that makes the water evaporate fast. So, you will have to get a new, suitable cap. Also, deposits clogging the radiator can lead to overheating very quickly. So, keeping the radiator clean will reduce the chances of overheating.

John Deere 4066r Problems: are they a deal breaker?

The aforementioned John Deere 4066R problems will not be a deal breaker. These are minor problems that happen on a minimal scale. Also, they are not exclusive to this powerful tractor. If you maintain this tractor, you will have a farming machine that lasts for decades.

This compact tractor from John Deere can finish the relevant tasks fast due to its advanced hydrostatic transmission lift. Also, all its unique features won’t make it a thirsty machine; fuel efficiency features back it.

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( Farming Equipment Expert )

Marvin is an expert in farming equipment with a strong background in agricultural engineering. He graduated from Kansas State College of Agriculture, where he received a degree in Agricultural Engineering and specialized in farm equipment design and maintenance.