John Deere 6620 Combine Parts
The John Deere 6620 combine, produced from 1979 to 1988, was a popular conventional combine known for its reliability and straightforward design. It featured engine HP ranging from 155-175 and header widths up to 30 feet, making it a versatile machine for various farm sizes. Its conventional separator system provided efficient threshing and separation for a variety of crops.
The John Deere 6620 was introduced in 1979 as part of the 20 Series combine harvesters, replacing earlier models and establishing itself as a workhorse in the agricultural industry. Production continued through 1988. The 6620 was powered by a John Deere 6.8L (414 cu in) diesel engine, producing between 155 and 175 horsepower depending on the year. This combine uses a conventional threshing system, featuring a 6-bar, 38-inch wide cylinder for effective grain separation. The grain tank capacity is approximately 150 bushels, and the unloading auger could unload at a rate of roughly 45-50 bushels per minute. Available header widths ranged from 13 feet to 30 feet, allowing farmers to optimize harvesting for their specific field conditions. Chopper and spreader options were available to manage crop residue effectively. The cab was designed for operator comfort and included features such as air conditioning and adjustable seating. The 6620 excelled at harvesting a variety of crops, including wheat, soybeans, corn, and other small grains, making it a versatile choice for many farming operations.
Specifications
| Engine | John Deere 6.8L (414 cu in) 155-175 HP Diesel |
|---|---|
| Separator Type | Conventional - 6-Bar, 38-inch wide cylinder |
| Grain Tank | 150 bushels |
| Unloading Rate | 45-50 bu/min |
| Header Widths | 13-30 ft |
| Fuel Capacity | 80 gallons |
| Weight | Approx. 16,000 lbs |
| Years Produced | 1979-1988 |
Maintenance Tips
- Concave Adjustment: Regularly check and adjust concave clearance to ensure optimal threshing and minimize grain loss. Follow the operator's manual recommendations for different crop types.
- Belt and Chain Tension: Inspect belt and chain tension regularly. Loose belts and chains can cause slippage and reduced efficiency, leading to premature wear and damage.
- Sieve and Chaffer Cleaning: Keep sieves and chaffers clean to ensure proper separation of grain from chaff. Regularly clean them to prevent blockages and maintain optimal performance.
- Bearing Greasing: Follow the recommended greasing schedule for all bearings. Proper lubrication is crucial for extending the life of bearings and preventing costly repairs.
History & Background
The John Deere 6620 was released in 1979 as a component of the John Deere 20 series combine line. It refined the conventional combine design and offered increased horsepower and capacity compared to prior generations. The 6620 is remembered as a dependable and cost-effective option for many farmers.
Frequently Asked Questions
What engine is in the John Deere 6620?
The John Deere 6620 is equipped with a John Deere 6.8L (414 cu in) diesel engine that produces between 155 and 175 horsepower depending on the year.
What is the grain tank capacity on a 6620?
The grain tank capacity on a John Deere 6620 is approximately 150 bushels, and the unloading rate is around 45-50 bushels per minute.
What type of separator does the 6620 have?
The John Deere 6620 utilizes a conventional threshing system, featuring a 6-bar, 38-inch wide cylinder for efficient grain separation.
What are common parts needed for the 6620?
Common wear parts for the John Deere 6620 include concaves, rasp bars, belts, chains, bearings, auger fingers, and sickle sections.

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