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.

AH127728 - Tank Loading Auger
SKU: AH127728
25 in stock

AH127650 - Upper Tailings Auger
SKU: AH127650
8 in stock

AH12678 - Clean Grain / Tailing Elevator (Solid) Door
SKU: AH12678
32 in stock

AH123930 - "Donut" Auger Tube
SKU: AH123930
20 in stock

AH123929 - Unloading ; Vertical Auger
SKU: AH123929
19 in stock

AH122717 - Auger End Gungeon
SKU: AH122717
37 in stock

AH122335 - Lower Tailings Auger
SKU: AH122335
15 in stock

AH11794 - Clean Grain / Tailing Elevator (Perforated) Door
SKU: AH11794
4 in stock

AH114715 - Rear Tank Cross Auger
SKU: AH114715
10 in stock

AH112452 - Auger End
SKU: AH112452
35 in stock

AH112164 - Clean Grain (w/o Yoke & Lever) Elevator
SKU: AH112164
12 in stock

AH112077 - Tailings Elevator Housing
SKU: AH112077
12 in stock

AH103727 - Rear Tank Cross Auger
SKU: AH103727
5 in stock

AH87289 - Muffler
SKU: AH87289
15 in stock

AH87288 - Muffler
SKU: AH87288
5 in stock

JD8947 - Bearing
SKU: JD8947
273 in stock

JD8524 - Ball Bearing
SKU: JD8524
95 in stock
JD8257 - Bearing Cup
SKU: JD8257
250 in stock

JD8237 - Bearing Cup
SKU: JD8237
250 in stock
AT23189 - Ball Bearing
SKU: AT23189
Out of stock

AT20703 - Rear Axle Shaft Seal
SKU: AT20703
544 in stock

AH89023 - Oil Seal
SKU: AH89023
60 in stock

RE11410 - Valve Rotator
SKU: RE11410
288 in stock

R83021 - Exhaust Manifold Gasket
SKU: R83021
2162 in stock
