Help! My John Deere X739 ran into problems.. (professional mechanic’s fixes)

The John Deere X739 is a part of the X700 Series, produced from 2013 onwards, and is a garden tractor revered for its four-wheel drive and four-wheel steer, powered by a 25.5HP Kawasaki engine. This lawn tractor, assembled in Horicon, Wisconsin, USA, was purposed for versatile residential yard tasks such as mowing, snow blowing, and leaf bagging, equipped with optional attachments like a 48″ to 60″ mid-mount mower deck and a snowblower. Its notable mechanical features include hydrostatic power four-wheel steering and an internal wet disc brake system, making it a robust choice for homeowners desiring a multifunctional lawn care solution.

The topic of troubleshooting common problems with the John Deere X739 is crucial whether you’re contemplating a purchase or are a current owner facing challenges. Diving into the prevalent problems and their remedies will help in discerning the practicality of this model. Let’s delve into the most common John Deere X739 problems, understand their roots, and explore how you can rectify them.

Igra-World, with its seasoned mechanics boasting decades of hands-on experience, has been at the frontier of addressing lawn tractor challenges. Our clientele often echo concerns about the truck, with one remarking, “The versatility seemed promising, but the performance in each task was a letdown.” Through diligent research, customer feedback, and real-world troubleshooting, we’ve compiled a trove of solutions for the common hitches you might encounter with this model.

How to troubleshoot the most common issues:

Engine starting difficulties (severity: high) – Ensure the tank has gasoline, use the correct fuel grade, and check for any spark plug issues or faulty safety switches; a thorough inspection and rectification of these elements should solve the problem.

Inadequate snow-blowing capacity(severity: medium): Consider inspecting the snow blower attachment for any blockages or damages; you might need to replace or service the snow blower attachment.

Unimpressive mowing performance (severity: medium): Check the mower deck for levelness, and sharpness of blades, and ensure that the tires are properly inflated to avoid uneven cuts and lawn damage.

Hydrostatic transmission noise (severity: low): Regularly check the transmission fluid levels and consider consulting a professional for a thorough transmission inspection.

Difficulty in changing attachments(severity: low*)– Ensure that the attachment brackets and latching mechanisms are free of debris and are well-lubricated for ease of change.


1. Engine Starting Difficulties

The most common culprits causing engine starting problems are a lack of fuel, incorrect fuel grade, clogged fuel system, faulty spark plug wire, or a depressed brake pedal not registering correctly.

Delving into the causes, it’s essential to understand is powered by a 25.5HP Kawasaki 745cc 2-cyl gasoline engine, and has a fuel tank capacity of 5.2 gallons. This impressive engine necessitates quality fuel to function optimally—ensuring there’s adequate fuel in the tank, and the right fuel grade is crucial. A clogged fuel system or dirty fuel filters could impede fuel delivery, stifling the engine’s attempt to start. On the electrical side, a faulty spark plug wire could disrupt the ignition process, while on the mechanical side, the brake pedal needs to be depressed for the engine to start—a safety feature to prevent accidental starts. If the brake pedal isn’t registering correctly, it could hinder the engine starting process. Ignition problems are also a common issue; a faulty ignition switch or problematic spark plugs could be the barrier between you and a smoothly running engine. Moreover, issues like a damaged starter motor, a weak battery, or a faulty starter solenoid are also often at play when the engine refuses to budge.

How to Fix Engine Starting Difficulties:

  1. Check Fuel Levels: Ensure the fuel tank has gasoline; if it’s empty, fill it with fresh gasoline.
  2. Verify Fuel Grade: Use the correct fuel grade as per the manufacturer’s guidelines; if unsure, refer to the user manual.
  3. Inspect Spark Plug Wire: Check the spark plug wire for any damage; replace if necessary.
  4. Depress Brake Pedal: Press the brake pedal down firmly before attempting to start the engine.
  5. Check the Fuel System: Look for any blockages in the fuel system; if uncertain, consider consulting a professional mechanic.
  6. Replace Dirty Fuel Filters: Replace any dirty fuel filters with new ones to ensure smooth fuel flow.
  7. Inspect Ignition System: Check the battery, ignition switch, and spark plugs; replace or fix any faulty components.
  8. Check Starter Motor and Battery: Examine the starter motor and battery for any issues; replace or charge them accordingly.
  9. Consult a Professional Mechanic: If the problem persists or if you’re unsure about any steps, don’t hesitate to consult a professional mechanic for a thorough inspection and rectification of the problem.

2. Inadequate Snow Blowing Capacity

The most common culprits causing inadequate snow-blowing capacity are blockages, damage to the snow blower attachment, and insufficient engine power.

The lawn tractor is equipped with either a 47″ or 54″ snow blower attachment. The 54″ snow blower, priced around $4300, includes a hydraulic option to control both the direction and height of snow throw, which is crucial for effectively clearing snow, especially in larger or hilly areas. The 47″ snow blower is about $400 cheaper and might be a better fit if you suspect the engine might struggle with the larger attachment. Your local John Deere dealer should be able to provide advice on which snow blower would be suitable for your X739, considering the power of its engine and the size of the area you need to clear.

How to Fix Inadequate Snow Blowing Capacity:

  1. Inspect the Snow Blower Attachment: Check for any blockages in the snow blower attachment that might be hindering its performance. If you find damage, consider ordering replacement parts like a new auger or a new blower fan from a reputable parts dealer.
  2. Check the Engine Power: Ensure that the engine is delivering enough power to operate the snow blower attachment effectively. If you are using a 54″ snow blower, ensure that your engine has adequate power to handle this larger attachment.
  3. Consult Your Local Dealer: If you’re unsure about the suitability of your snow blower attachment, consult with your local John Deere dealer. They might have suggestions or recommendations based on your specific situation and the conditions in your area.
  4. Regular Maintenance: Regular maintenance can prevent many common issues. Check and replace the oil, inspect the belts, and keep the snow blower attachment clean to ensure it operates effectively.
  5. Upgrade Your Snow Blower Attachment: If your snow blower attachment is old or inadequate for your needs, consider upgrading to a newer or larger model that can handle the snow-clearing tasks required.
  6. Check the Mounting: Ensure that the snow blower is properly mounted and the “anti-rotation pin” is correctly positioned to avoid any operational issues.

3. Unimpressive Mowing Performance

The most common issues causing unimpressive mowing performance are debris on the mower deck, uneven tire pressure, and dull or damaged blades. Misaligned or damaged belts and pulleys could also contribute to the problem.

For the overview of the problem, a myriad of factors can lead to an unimpressive mowing performance. The X739 model comes with an option among a 48″, 54″, or 60″ mid-mount mower deck which, if not maintained properly, could lead to uneven cuts and lawn damage. One common issue is the accumulation of debris on the mower deck or in the sheaves, causing the blades to become unbalanced and create a vibration—this is something that could be exacerbated if the blades are dull or damaged. If these conditions persist, it might result in the mower belt or pulleys getting damaged, requiring replacements to restore optimal functionality. Uneven tire pressure is another culprit—when the tires are not inflated to the recommended pressure, it can cause the deck to tilt during mowing, leading to uneven cuts. Besides, the powerful 24.5 horsepower diesel engine of the X739 is designed for heavy-duty mowing and landscaping tasks, yet, if the mower’s RPM is not set or maintained correctly, it could significantly hinder the performance. Additionally, grass residue build-up under the deck over time could hinder performance, especially in damp conditions, as it requires more power to cut through—something that’s been noted by users in the Pacific Northwest.

How to Fix Unimpressive Mowing Performance:

  1. Inspect the Mower Deck: Check for debris on the mower deck and in the sheaves. Clean off any grass clippings, leaves, and other debris that might have accumulated. Also, inspect the blades for sharpness and balance—sharpen or replace them as necessary.
  2. Check Tire Pressure: Ensure that the tires are inflated to the recommended pressure to prevent the deck from tilting during mowing.
  3. Inspect Belts and Pulleys: Look for any signs of wear, tear, or damage on the mower belt and pulleys. Replace any damaged parts to ensure smooth operation.
  4. Maintain Correct RPM: Ensure that your mower is operating at the correct RPM. Typically, commercial mowers are designed to optimize performance at 3600 RPM. If your mower’s RPM dips below this, it could affect the mowing performance adversely.

4. Hydrostatic Transmission Noise

The most common cause of hydrostatic transmission noise is inadequate lubrication due to low transmission fluid levels, followed by potential mechanical faults within the transmission system itself.

Issues of hydrostatic transmission noise in the lawn tractor can primarily be traced back to the level and quality of transmission fluid in the system—ensuring it’s within the recommended range is crucial. This lawn tractor operates on a hydrostatic transmission which relies heavily on fluid to function smoothly. The transmission is designed for four-wheel drive and hydrostatic power four-wheel steering, which adds to its complexity and the importance of maintaining proper fluid levels. When the fluid level drops or the fluid quality deteriorates, it can cause excessive noise especially when shifting gears, indicating a lack of adequate lubrication within the system. Furthermore, the transmission fluid works in tandem with internal wet disc brakes, and any inadequacy can lead to not just noise, but decreased performance or even damage. If you’ve noticed a decline in performance, this might be a related issue—low fluid levels can hinder the transmission’s ability to transfer power from the engine to the wheels, leading to poor performance or loss of power. Mechanical faults or damage within the transmission—though less common—can also be a source of noise and are worth inspecting if fluid levels are found to be adequate.

How to Fix Hydrostatic Transmission Noise:

  1. Check Transmission Fluid Levels: Ensure the fluid level is within the recommended range; top it off with a good-quality transmission fluid if necessary.
  2. Inspect the Transmission: If the fluid level is adequate, yet the noise persists, consider consulting a qualified technician to inspect the transmission for any potential faults or damage.
  3. Regular Maintenance: Keep a regular check on the transmission fluid levels and the quality of the fluid. Replace it with a good-quality oil if necessary, as per the manufacturer’s recommendations.

5. Difficulty in Changing Attachments

The primary issues surrounding the difficulty in changing attachments relate to debris accumulation and insufficient lubrication of the attachment brackets and latching mechanisms.

The lawn mower is adaptable with a variety of attachments such as 48″, 54″, and 60″ mid-mount mower decks, and snow blowers. The versatility of this lawn tractor could lead to frequent changes in attachments, potentially causing wear and accumulation of debris in the attachment brackets and latching mechanisms over time. Such complications could hinder the ease of changing attachments. The latching mechanisms and brackets are crucial as they ensure a secure attachment fit, allowing for efficient operation—whether it’s mowing, snow blowing, or other tasks. Lack of proper maintenance in these areas could lead to a laborious attachment change process, affecting the overall productivity and user experience.

How to Fix Difficulty in Changing Attachments:

  1. Inspect and Clean: Firstly, inspect the attachment brackets and latching mechanisms for any debris or dirt accumulation. Clean them thoroughly using a brush or a cloth to remove any obstructing materials.
  2. Lubricate: Apply a suitable lubricant to the attachment brackets and latching mechanisms to ensure smooth operation. Lubrication minimizes friction, making it easier to change attachments.
  3. Check for Wear: Examine the latching mechanisms and brackets for any signs of wear or damage. If any worn or damaged parts are found, replace them to ensure a secure and easy attachment change.
  4. Ensure Correct Attachment Fit: Make sure that the attachments are correctly fitted and securely latched before operating the lawn tractor. Correct attachment fit is crucial for the safe and efficient operation of the lawn truck.
  5. Consult the Manual: For any additional guidance on changing attachments, refer to the user manual. The manual provides detailed instructions and maintenance tips to ensure ease of changing attachments.

If you don’t already own one, should you buy it?

The purchase of X739 hinges upon your personal needs and the extent of tasks you wish to tackle. It’s a top-tier garden tractor with four-wheel drive and four-wheel steering, powered by a robust 25.5HP Kawasaki engine. This American-made machine stands out for its versatility in handling a variety of residential yard tasks—mowing, snow blowing, and leaf bagging—thanks to its optional attachments like a mid-mount mower deck (48″ to 60″) and a snow blower.

The X739 showcases impressive mechanical attributes such as hydrostatic power four-wheel steering and an internal wet disc brake system. These features contribute to superior control and ease of operation in diverse terrains, be it maneuvering through tight spaces or tackling steep inclines. Besides, users appreciate its high-quality build and durability, affirming a long-lasting performance even after years of use. The power steering, in particular, receives praise for making the operation effortless.

On the flip side, users have pointed out some areas of concern. The most recurrent issues pertain to engine starting, inadequate snow blowing capacity, unimpressive mowing performance, hydrostatic transmission noise, and difficulties in changing attachments. While these issues are notable, they are solvable with regular maintenance and the correct remedial measures. For instance, ensuring the use of recommended fuel grade, keeping the mower deck clean, and maintaining correct tire pressure can significantly improve the performance and user experience.

Comparatively, a tractor like the Kubota BX2380, which also boasts a 4WD and similar horsepower, could be an alternative. However, it lacks the four-wheel steering feature of the X739, which might affect maneuverability in tighter spaces.

Why trust Igra World?

Harnessing years of lawn care expertise, our seasoned mechanics at Igra World embarked on a meticulous journey of troubleshooting common hitches with the X739—engine starting issues, uneven cutting, loss of power, engine misfires, and mower belt slippage to name a few. Our process commenced with identifying the roots of these snags, followed by checking key components such as sheaves, pulleys, air filters, and ignition systems. We delved into cleaning and replacing faulty parts, ensuring each tractor regained its optimal performance. Amidst a symphony of engines misfiring and then smoothly igniting post-tinkering, our editors, with grease-stained hands, meticulously crafted a troubleshooting guide. Resolving each hiccup became a testimony to the robust yet maintainable design of this model. Our guide now stands as a beacon of self-help for the owners, underscoring our belief in empowering lawn enthusiasts through knowledge and a well-maintained tractor.

About Jeff Henderson

Have a question regarding your lawn tractor? Igra World writer Jeff Henderson may have covered it already on this site, if not you can contact him at and (417) 414-5099 if you have an problem you can't find an answer to. Jeff is a part time tractor mechanic and landscaping company owner who lives in Springfield, Missouri. He has over 10 years of experience in tractor repair and small engine repair, and has worked with John Deere, Husqvarna, Toro, Troy Bilt, Cub Cadet and Kubota equipment.

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