Case IH 666 Tractor Parts
666 parts and accessories
The Case IH 666 tractor, manufactured from 1971 to 1976, was a popular choice for farmers due to its reliable performance and versatility. Powered by a robust International Harvester 304 cubic inch engine producing approximately 66 horsepower, and delivering around 58 PTO horsepower, the 666 was well-suited for various agricultural tasks. Its combination of power and practicality made it a valuable asset on many farms.
The Case IH 666 was part of the International Harvester line of tractors, produced from 1971 to 1976. It was designed as a mid-size utility tractor capable of handling a wide range of farm tasks. Under the hood lies an International Harvester 304 cubic inch gasoline engine, rated at approximately 66 horsepower. Some models were also available with a diesel engine option. The 666 utilized a gear-type transmission, offering options for either 8 forward and 4 reverse speeds or a Torque Amplifier (TA) providing increased flexibility. The rear PTO delivered around 58 horsepower, typically operating at 540 RPM. Its hydraulic system had a capacity of around 9 GPM, typically with two remote valves. The 3-point hitch was a Category II, providing a lift capacity of around 3500 lbs. Common applications included row crop work, hay baling, livestock feeding, and light tillage operations. The 666 distinguished itself from smaller models with its larger engine and heavier build, providing more power for demanding tasks.
Specifications
| Engine | International Harvester 304ci 66 HP Gas or Diesel |
|---|---|
| PTO HP | 58 HP @ 540 RPM |
| Transmission | Gear Drive, 8F/4R or with Torque Amplifier (TA) |
| Hydraulics | 9 GPM, 2 remotes |
| 3-Point Hitch | Category II, 3500 lbs lift capacity |
| Fuel Capacity | 24 gallons |
| Weight | 6,240 lbs |
| Years Produced | 1971-1976 |
Maintenance Tips
- Engine Oil & Filter: Change the engine oil and filter every 100-125 hours of operation using a high-quality oil that meets the manufacturer's specifications.
- Hydraulic System: Regularly inspect hydraulic fluid levels and check for leaks. Change the hydraulic fluid and filter every 500 hours, or as recommended by the manufacturer.
- Fuel System: Use clean, fresh fuel. Inspect and clean the fuel filter regularly to prevent clogs. Consider adding a fuel stabilizer during seasonal storage.
- Seasonal Storage: Before storing the tractor for the off-season, drain the fuel tank (if gasoline) or add a fuel stabilizer (if diesel). Disconnect the battery and store it in a cool, dry place. Grease all lubrication points to prevent rust.
History & Background
The Case IH 666 was introduced in 1971 as part of International Harvester's lineup of utility tractors. While it didn't undergo major redesigns during its production run, it proved to be a reliable and popular model. The 666 played a significant role in providing farmers with a versatile tractor option for various agricultural applications.
Frequently Asked Questions
What engine is in the Case Ih 666?
The Case IH 666 is equipped with an International Harvester 304 cubic inch gasoline or diesel engine, producing approximately 66 horsepower.
What is the PTO horsepower on a 666?
The Case IH 666 delivers around 58 PTO horsepower, operating at 540 RPM.
What oil filter fits the 666?
The Case IH 666 typically uses a Fram PH8A or equivalent oil filter. Cross-references include Wix 51068 and NAPA 1068. Verify fitment based on your specific engine configuration.
What are common parts needed for the 666?
Commonly needed parts for the Case IH 666 include engine oil filters, fuel filters, hydraulic filters, fan belts, radiator hoses, hydraulic cylinder seals, steering components (tie rod ends), clutch disc and pressure plate, and PTO shaft seals.

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