What Engine Is in a John Deere 425? Verified Answer!

What Engine Is in a John Deere 425? Verified Answer!

Have you ever wondered what makes the John Deere 425 such a popular tractor? Aside from its versatility and functionality, one of its most impressive features is its engine. 

One question that often arises in this regard is: what engine powers the John Deere 425 tractor? Read on as I’ll provide every information you should know about the John Deere 425 engine. 

What Engine is in a John Deere 425

The John Deere 425 garden tractor is equipped with a 20-horsepower Kawasaki FD620D engine. This liquid-cooled V-twin gasoline engine has a displacement of 617 cc and features a horizontal-shaft design. 

Early versions of this engine used plastic cam gears, but steel cams were introduced starting with engine serial number 149283. Here are some key specifications for the John Deere 425 engine:

  • Power: 20 hp (14.9 kW)
  • Fuel System: Carburetor
  • Air Cleaner: Paper element with pre-cleaner
  • Compression Ratio: 9:1
  • Rated RPM: 3550
  • Idle RPM: 1450-3550
  • Starter: Electric, 12 volts, 1.1 hp (0.8 kW)
  • Coolant Capacity: 3 quarts (2.8 liters)
  • Sparkplug Gap: 0.030 inches (0.762 mm)
  • Engine Oil Capacity: 1.6 quarts (1.5 liters)

The John Deere 425 is a reliable garden tractor manufactured by John Deere, and its engine plays a major role in its performance and durability. If you’re looking for replacement options or upgrades, consider exploring the Kawasaki FD750D 27 HP engine kit from Repower Pros, which comes with easy installation instructions and a 3-year warranty.

What Is the Fuel Consumption of John Deere 425?

The John Deere 425 garden tractor, equipped with a 20-horsepower Kawasaki FD620D engine, has a fuel tank capacity of 6.5 gallons (24.6 liters).

See also  Is a John Deere 1020 a Good Tractor?

Below is a brief information on the John Deere 425 fuel consumption rate:

  • At low idle, the fuel consumption is approximately 0.94 gallons per hour (3.6 liters per hour).
  • At high idle, it consumes around 1.57 gallons per hour (5.9 liters per hour).

Meanwhile, understand that the fuel consumption rate varies based on factors such as load, terrain and maintenance. However, the above information is just to serve as a hint on its consumption rate and it is based on my own research.

What Is the Top Speed of John Deere 425?

The John Deere 425 garden tractor, which is part of the 400 series, offers a top speed of approximately 8.5 miles per hour (13.7 kilometers per hour). This versatile machine, powered by a 20-horsepower Kawasaki FD620D engine, is designed to tackle various lawn and garden tasks with ease. 

Whether you’re mowing, hauling, or performing other yard work, the John Deere 425 delivers reliable performance and durability 23.

What Is the Weight of John Deere 425?

The John Deere 425 garden tractor weighs approximately 805 to 900 pounds. Here are some components that make up the overall weight of the John Deere 425:

  • Engine: Equipped with a 20-horsepower Kawasaki FD620D engine.
  • Fuel Tank Capacity: 6.5 gallons (24.6 liters).
  • Transmission: Hydrostatic.
  • Wheelbase: 2WS (Two-Wheel Steering): 50.4 inches (128 cm).
  • AWS (All-Wheel Steering): 49.4 inches (125 cm).
  • Front Tire Size: 16×7.50-8.
  • Rear Tire Size: 23×10.50-12.

These components put together are what make up the approximate weight of 900 pounds for the John Deere 425. 

What Is the Price of John Deere 425?

The John Deere 425 garden tractor was originally priced at $8,995 back in 1995. However, If you’re interested in purchasing a used John Deere 425, you can explore options at John Deere dealerships or online platforms. 

For instance, I found a listing where a used John Deere 425 is available for $5,995. This particular unit has 1729+ hours of use, power steering, a 60″ mower deck, and even comes with a front 56″ blade and a cab.

See also  John Deere 333g Problems – Best Solutions And Some Ways To Make It Last Longer

However, keep in mind that prices can vary based on condition, location, and any additional attachments or accessories.

Common Problems With Kawasaki FD620D Engines and How to Solve Them

John Deere 425

The Kawasaki FD620D engines, while reliable, can encounter a few common issues.

Over-Revving with Age

Some users have reported that these engines tend to over-rev as they age. The cause may be related to the governor spring becoming brittle due to repeated heat and cooling cycles over the years.

The spring’s tension might change, affecting the engine’s RPM control. Replacing the control panel or adjusting it carefully to regain proper RPM control. Fresh parts might help if the existing ones are aged.

Head Gasket Failures

Head gasket failures can occur, leading to coolant leakage or compression loss. Regular maintenance and proper torque during assembly and monitoring coolant levels can prevent this issue.

Starting Problems

If your Kawasaki FD620D engine doesn’t start, check for:

  • A dead or weak battery.
  • A faulty starter motor or solenoid.
  • A bad ignition switch or wiring.

Check and address these components to ensure reliable starting.

Fuel System Issues

Clogged fuel filters, dirty carburetors, or fuel pump malfunctions can affect performance. Regularly clean or replace filters, inspect the fuel system and ensure proper fuel flow.


Overheating due to low coolant levels or dirty radiator fins is also another problem with the Kawasaki FD620D engines. To resolve this, ensure proper coolant levels and clean the radiator fins to prevent overheating, Inspect hoses, belts, and the water pump.

How Do I Maintain My Kawasaki FD620D Engine?

Maintaining your Kawasaki FD620D engine is essential for ensuring its optimal performance and longevity. Here’s how you can keep your engine running smoothly, broken down into key maintenance areas:

  • Regular Oil Changes: Adhere to the recommended intervals for changing the engine oil, using high-quality oil suitable for air-cooled engines. It’s important to frequently check the oil level and top up as needed, ensuring the engine operates smoothly.
  • Air Filter Maintenance: The air filter should be cleaned or replaced regularly to prevent clogging, which affects performance and fuel efficiency. Additionally, inspect and clean the pre-cleaner to ensure optimal air flow.
  • Spark Plug Care: Check the condition of the spark plug and replace it if it’s worn out or fouled. Setting the correct spark plug gap according to the manufacturer’s specifications is crucial for optimal ignition.
  • Cooling System Inspection: Keep an eye on the coolant level, topping up with the recommended coolant mixture to prevent overheating. Cleaning the radiator fins is also vital to ensure efficient heat dissipation.
  • Fuel System Attention: Inspect the fuel lines, filters, and the fuel pump regularly, and use fresh, clean fuel to avoid carburetor issues. This ensures a steady and reliable fuel supply for the engine.
See also  How to Winterize a John Deere Riding Mower?

Other Maintenance Recommendations

  • Governor Adjustment: Ensure the governor spring is in good condition and adjust the governor as necessary to maintain proper RPM control. This helps in achieving a balance between performance and fuel efficiency.
  • Belt and Pulley Inspection: Drive belts should be checked for wear or damage and replaced if necessary. Pulleys should also be inspected to ensure they rotate smoothly, which is essential for efficient power transmission.
  • Regular Lubrication: Grease all moving parts, including pivot points and linkages, to reduce friction and wear. The throttle and choke cables should also be lubricated for smooth operation.
  • Cooling Fins Cleaning: The cooling fins on the engine and cylinder head should be kept clean of debris, using compressed air or a soft brush, to maintain the engine’s temperature within operational limits.
  • Professional Servicing: Schedule periodic professional servicing to address any unusual noises, leaks, or performance issues promptly. This ensures that potential problems are identified and resolved before they lead to significant damage or costly repairs.


The John Deere 425 is an excellent choice for anyone looking for a durable, reliable, and powerful tractor. With its Kawasaki FD620D engine, the John Deere 425 can tackle any job with ease. 

If you’re looking for a machine that can handle your toughest tasks, then the John Deere 425 is the perfect option for you. There’s no doubt about the quality of this tractor!

About Author

Bruno C.

I am a professional content writer, a pet lover, an agriculture enthusiast and an innovative thinker. I appreciate performing the research required to keep my articles relevant, current, and engaging, and I bring my industry expertise and experience to every project I tackle.

Leave a Reply

Your email address will not be published. Required fields are marked *