Case 650K, 750K, 850K Crawler Dozer Repair Manual

The Case 650K, 750K, and 850K crawler dozers are part of Case’s K-Series lineup, engineered for strength, efficiency, and operator-focused productivity. These mid-sized dozers provide excellent balance between horsepower, weight, and hydraulic responsiveness, making them ideal for construction, grading, land clearing, and site preparation.

Introduction
The 650K, 750K, and 850K combine rugged Case engineering with hydrostatic power delivery, ensuring smooth operation and precise control. Operating weights range from 18,200 lb on the 650K up to over 22,000 lb on the 850K, providing a stable platform for heavy pushing and grading.

Distribution Systems
All three models utilize dual-path hydrostatic drive systems for power distribution, controlled through a single-lever joystick. This setup allows independent track control for excellent maneuverability, reduced operator fatigue, and efficient load handling in variable ground conditions.

Power Production
The Case 650K and 750K are powered by the Case Family III 445T/M2 4-cylinder diesel engine, delivering 80 HP (650K) and approximately 90–96 HP (750K). The larger 850K is equipped with the Case Family III 668T/M2 6-cylinder diesel engine, producing around 96 HP net. These Tier II compliant engines are designed for fuel efficiency, strong torque output, and long service life.

Power Train
A hydrostatic transmission provides infinite variable speeds up to 5.5 mph, enabling seamless adjustment to task requirements. The hydrostatic powertrain eliminates gear-shifting, offering smoother operation in both heavy dozing and fine grading applications.

Travelling
Track widths vary across the models: 16 in on the 650K, 18–20 in on the 750K, and 24 in on the 850K. Track ground contact spans approximately 88–110 in, ensuring strong traction and flotation in soft or uneven terrain. LGP (low ground pressure) configurations are available for sensitive soil conditions.

Body and Structure
The K-Series dozers feature robust mainframes and undercarriages designed for durability. Operator safety and comfort are enhanced with ROPS canopy options, ergonomic control placement, and excellent visibility for all-day productivity.

Tool Positioning
Blade control is responsive and precise, with fingertip joystick operation. PAT (power-angle-tilt) blades are standard on most configurations, offering multi-directional positioning for grading and finish work.

Working Arm
The dozers are fitted with straight or PAT blades, depending on the configuration. Capacities range from 2.0 yd³ on the 650K to 2.6 yd³ on the 850K. Blade widths vary from 8 ft to 9 ft, with lift and tilt functions supported by the hydraulic system.

Tools and Couplers
Rear-mounted ripper and winch options are available, extending the machine’s versatility for site clearing, soil preparation, and utility applications.

Electrical Schematics
A 12-volt negative ground system with a 65-amp alternator provides reliable starting and auxiliary electrical support. The system is designed for easy servicing and durability in demanding field environments.

Hydraulic Schematicas
The open-center hydraulic system delivers approximately 20–22 GPM at 3,025 psi (650K), with higher flow on the 750K and 850K models. A hydraulic reservoir capacity of 20 gal supports cooling and responsiveness, ensuring smooth blade and attachment control during sustained operations.

Key Highlights

• 650K: 80 HP 4-cyl diesel, ~18,200 lb, 16-in tracks, 2.0 yd³ blade
• 750K: ~90–96 HP 4-cyl diesel, ~18,900 lb, 18–20 in tracks, 2.3 yd³ blade
• 850K: ~96 HP 6-cyl diesel, ~22,000 lb, 24-in tracks, 2.6 yd³ blade
• Dual-path hydrostatic drive with single-lever control
• Fuel capacity up to 50 gallons; Hydraulic capacity up to 20 gallons
• Blade widths 8–9 ft with PAT (power-angle-tilt) configuration
• ROPS operator canopy with ergonomic controls
• Optional ripper and winch attachments for added versatility