Description

Champion 720, 710A, 780, 780A 1991 Training Manual – What a Real Tech Needs

Champion 720, 710A, 780, 780A 1991 Training Manual. If you are turning wrenches on a Series III motor grader from Champion, you already know the aftermarket junk leaves you guessing on pilot pressures and clutch pack clearances. This is the original training manual used inside the factory – 57 pages of oil circuit schematics, solenoid valve operation, and the exact sequence for setting the drawbar and circle. No reprints or third-party interpretations.

Front Axle: Models 710 to 750A – Alignment and Oscillation

The front axle section covers the 710 through 750A models, and includes the toe-in adjustment procedure and wheel lean linkage check. Page 6 has the disassembly order for the kingpin and bushing replacement. If you have a 780 or 780A, skip to page 10 – the axle housing and steering knuckle are larger. Both designs use the same basic oscillation stop, but the 780 uses a heavier thrust bearing. Do not mix parts between models without confirming the part numbers.

Hydraulic Main System – Solenoid Valve Logic

This manual dives into the main hydraulic circuit starting on page 14. You get the flow path from the main pump through the unloading valve and into the pilot-operated solenoid bank. The solenoid-operated valves section on page 20 explains the electrical signals for blade lift, side shift, and articulation. If you are diagnosing a slow blade or a drop in charge pressure, trace the oil flow through the sequence valves – the manual labels every port and spring setting. That is the kind of detail you will not find in a generic service guide.

3 Major Systems Covered: Transmission, Clutch, Brakes

Oil supply circuits for the 8400 transmission and the double clutch assembly are mapped with full-color flow arrows. The clutch section covers the 4-disc, 13.5-inch unit. Brake section: wet disc brakes and the accumulator-style brake system are both explained. Need the brake disc clearance? Page 52. The manual gives the assembly sequence and the torque pattern for the cover bolts. For the transmission, the neutral circuit is on page 36, first forward on page 38, first reverse on page 40. Each mode has its own oil path diagram.

Torque Specs and Assembly Tolerances

On page 26, the circle mounting and adjustment procedure includes the bolt torque values for the drawbar and the circle retainer. You also get the backlash spec for the circle drive. Every torque figure in this manual comes from the Champion engineering department in 1991 – not from a chinese translation. When the manual says 250 lb-ft, that is what you set your torque wrench to. Do not guess. Use the chart inside the rear cover for conversion if you need metric equivalents, but the original values are in imperial.

Source Authenticity – Why You Skip Aftermarket PDFs

This is not a photocopy of a copy. It is the original Champion training manual, printed in 1991 on recycled paper (as noted on page 1). The content was written for Champion dealer technicians who had to tear down and rebuild these graders in the field. Aftermarket manuals often omit the solenoid valve stack sequence or the MPLS (Movable Point Lift System) adjustments. This manual has all that. Compare the table of contents: Alta Elevación de Punto Fijo on page 22, Sistema de Elevación de la Cuchilla de Punto Móvil on page 24, and the six-wheel drive system on page 56. That is coverage you can trust.

Who Should Use This Manual

Home garage enthusiasts who own a Champion 720 or 780 grader and want to do their own hydraulic repairs. Shop owners who need a reference for their techs. Anyone who has been burned by a bad aftermarket wiring diagram will appreciate the solenoid coil resistance values listed in the hydraulic section. If you are restoring a Series III machine, this manual is the baseline for component identification and assembly order. Beginners: you will need a basic understanding of hydraulic circuits, but the flow paths are drawn clearly enough to trace with a highlighter.

Frequently Asked Questions

Does this manual include the engine section?

No. This is a chassis and drivetrain training manual. It covers the front axle, steering, hydraulics, blade assembly, transmission/clutch, brakes, and six-wheel drive system.

Are the torque values in inch-pounds or foot-pounds?

All torque values in the manual are given in foot-pounds (lb-ft) and are original factory specs from Champion.

Can I use this manual for the 710A model?

Yes, the 710A is included in the front axle coverage (pages 6-8) and all hydraulic systems are shared with the 720/780 series. The wiring and solenoid layout are identical for the machine series.

What if I need the part numbers for the brake discs?

The manual does not list part numbers. It is a training document explaining how the systems function and how to assemble/disassemble them. For specific part numbers, you will need the Champion parts catalog for your model year.

Related Manuals

• Champion 700 Series Grader Series III Training Manual
• Champion 700 Series Grader Series III Service Training Manual
• Champion Road Machinery 700 Series Service Training

The oil circuit for the 8400 Manual Transmission is detailed on pages 30-36. If you are troubleshooting a hard shift or slip in the Manual Transmission, you need this manual. Access the Factory Manual and get the real specs your bench needs.