New Holland TX66, TX68 Combine Pdf Repair Service Manual (p. Nb. 86603389)

New Holland TX66, TX68 Combine PDF Repair Service Manual (Publication No. 86603389)

When harvest conditions are constantly changing, combine performance depends on efficient threshing, clean grain separation and reliable power transmission. The New Holland TX66 and TX68 Combine Harvesters were engineered for professional grain producers requiring high output with minimal grain loss. Built around New Holland's proven Twin Flow™ threshing and separation system, these combines deliver excellent crop handling while maintaining grain quality across wheat, barley, corn, soybeans, canola and other cereal crops.

During long harvesting seasons, components such as the threshing drum, concaves, straw walkers, hydrostatic transmission, unloading auger and hydraulic systems operate under continuous heavy loads. This OEM Factory Repair Service Manual (Publication No. 86603389) provides dealership-level repair procedures covering diagnostics, inspection, adjustment, calibration and complete component overhaul, allowing technicians to restore original harvesting performance and reduce costly downtime during peak harvest.

Built for Large-Scale Grain Harvesting

The TX66 and TX68 were developed for farms demanding greater harvesting capacity without sacrificing grain quality. Their large-diameter threshing drum works together with the Twin Flow™ separation system to maximize grain recovery while reducing cracked kernels and straw damage. A spacious grain tank, high-capacity unloading system and hydrostatic drive enable continuous harvesting across large acreages with fewer interruptions.

Machine Information

Factory Workshop Coverage

Professional Workshop Procedures

• Adjust concave clearance according to harvested crop type.
• Synchronize threshing drum and separator drive components after repairs.
• Inspect straw walker bearings before every harvesting season.
• Calibrate cleaning fan speed to reduce grain losses.
• Service unloading auger drive assemblies and gearbox components.
• Test hydrostatic transmission pressure using OEM diagnostic procedures.
• Inspect feeder elevator chains and sprockets for excessive wear.
• Repair hydraulic steering and header lift systems.
• Diagnose electrical faults using complete factory wiring diagrams.
• Use exploded OEM illustrations during complete combine rebuilding.
• Apply factory torque specifications throughout all structural repairs.
• Perform complete harvesting performance tests before field operation.

Manual Specifications

Frequently Asked Questions

Which combine models are covered?

This OEM factory workshop manual covers the New Holland TX66 and TX68 Combine Harvesters (Publication No. 86603389).

Does the manual include Twin Flow™ threshing and separation repairs?

Yes. It includes complete procedures for the threshing drum, concaves, separator system, straw walkers, cleaning shoe and grain handling components.

Are hydrostatic transmission and hydraulic systems covered?

Yes. The manual contains complete servicing procedures for hydrostatic drive components, hydraulic pumps, steering circuits, valves and pressure testing.

Does the manual include electrical wiring diagrams?

Yes. Factory wiring diagrams, electronic diagnostic procedures and troubleshooting information are included.

Who should use this repair manual?

This manual is designed for New Holland dealership technicians, combine repair workshops, harvesting contractors, fleet maintenance teams and experienced mechanics servicing TX66 and TX68 combines.