1970–1975 J.I. Case 770, 870, 970, 1070, 1090, 1170, 1175 Tractor Shop Manual

This J.I. Case shop manual covers Series 770, 870, 970, 1070, 1090, 1170, and 1175 tractors. Gasoline engine coverage applies to the 770, 870, and 970; diesel engine coverage extends across all seven series.

PDF Search, Diagram Legibility, and Page Count

Search and navigation: An OCR text layer supports searches through the service chapters, but index coverage is incomplete, including no usable index text on PDF page 3. There are no embedded PDF bookmarks. Small wiring labels require enlargement, and some connector numbers remain indistinct.

Supplied as one printable, English-language PDF with 76 pages total, including one added cover page and 75 pages of manual content.

Engine, Drivetrain, and Hydraulic Service

This overview highlights selected service topics; the manual also covers Lanchester engine counter-balancer service and remote-cylinder breakaway couplings.

• Engine repair: Engine removal, cylinder-head service, valve adjustment, piston and sleeve inspection, crankshaft bearings, timing gears, and lubrication-system service.

• Fuel systems: Zenith carburetor overhaul, Bosch PES injection-pump timing, Roosa-Master nozzle testing and repair, and Garrett turbocharger inspection.

• Transmission and final drives: Step-by-step procedures for tractor splitting and clutch repair, plus Power Shift planetary overhaul, differential adjustment, and planetary final-drive service.

• Steering and brakes: Ross hydrostatic steering diagnosis, pump and control-valve overhaul, steering-cylinder repair, brake bleeding, and disc-brake service.

• Hydraulics and IPTO: Dual-pump flow testing, remote-valve service, independent PTO clutch repair, and Draft-O-Matic valve, rockshaft, and sensing-linkage adjustment.

• Electrical service: Gasoline and diesel wiring diagrams, Prestolite distributor service, charging-system tests, and Delco-Remy starting-motor test specifications.

The overhaul and diagnostic sections suit mechanics familiar with tractor repair who have access to lifting equipment, pressure gauges, a hydraulic flow meter, and the specified service tools.

Engine, Fuel System, and Turbocharger Service

Engine coverage extends to internal inspection and reassembly, with model-specific piston, sleeve, bearing, and valve data. Cylinder-head service includes staged tightening sequences and the Case A42393 torque-wrench adapter; the valve section distinguishes cold and hot clearances.

The diesel chapters cover injection timing, pump removal and installation, external speed and fuel-delivery adjustment, and nozzle opening-pressure, spray-pattern, and leakage tests. Referenced tools include the A43278 injector puller and A43277 nozzle-bore cleaning tool.

Service limits: Bosch governor work beyond minor speed adjustments is referred to an authorized Bosch Service Station. For the Garrett T-04 turbocharger on the 1170 and 1175, coverage includes testing, inspection, removal, installation, and lubrication priming; internal turbocharger disassembly is specifically not recommended.

Cooling-system coverage includes radiator removal, thermostat checks, and water-pump replacement. The water pump is supplied as a complete assembly, and the service section centers on assembly replacement.

Power Shift, Mechanical Transmission, and Final Drives

Power Shift coverage applies to the 770, 870, 970, 1070, and 1090. Its four-speed gearbox and three-speed planetary section provide 12 forward and four reverse ranges; the 1170 and 1175 use the eight-speed mechanical-shift arrangement.

The repair sections address the torque limiting clutch, individual Power Shift clutch packs, planetary components, control valves, and transmission shafts. Diagnosis includes clutch-port leakage checks and C2/C3 retard-valve synchronization using the Case A2743 Clutch Monitor and pressure switches.

The retard-valve discussion explains how incorrect synchronization can interrupt drive or briefly engage opposing clutches into a partial lockup.

Differential and axle variants: Separate procedures distinguish the 1175 differential before and after Serial No. 8715247, alongside the related 1170 and 970/1070 arrangements. Early and late planetary final drives are also treated separately, helping the buyer select the applicable procedure before disassembly.

Carrier-bearing preload and bevel-gear backlash are covered together. The manual explains why the differential shim packs must remain identified by side: their placement controls both adjustments.

Ross Steering and Brake Configurations

The 770, 870, 970, 1070, and late 1175 use a steering actuator; the 1090, 1170, and early 1175 use two external steering cylinders. Steering service includes model-specific rotor-to-stator inspection limits and the D44115 cylinder-gland spanner.

The 1175 Ross unit has lapped sealing faces whose finish and flatness are critical; scratches or burrs can compromise sealing.

Brake coverage distinguishes lever-operated double-disc assemblies from the power-assisted, self-adjusting caliper brakes on the 1090, 1170, and early 1175. Procedures include manual master-cylinder service, power-brake valve overhaul, hydraulic bleeding, and parking-brake adjustment.

Hydraulic Fault Isolation and Draft-O-Matic

The hydraulic test section evaluates the two pump sections separately and uses flow measurements to isolate leakage in the dual remote valve, IPTO clutch, and Power Shift clutches. This connects a hydraulic symptom to the relevant circuit before major components are removed.

Draft-O-Matic coverage follows the control valve through its operating positions and addresses lower sensing linkage, upper linkage, draft sensitivity, and rockshaft-cylinder service. IPTO coverage includes clutch and brake operation, reduction gears, and single- or dual-speed output arrangements.

Wiring and Hydraulic Illustrations

Illustrations extend through Fig. 233 and include exploded assemblies, cross-sections, test setups, and adjustment drawings. Electrical sections distinguish Prestolite and Delco-Remy charging equipment.

Useful references include the gasoline wiring diagram in Fig. 90, the typical diesel wiring diagram in Fig. 92A, the Power Shift hydraulic schematic in Fig. 118, the IPTO clutch/brake fluid-flow section in Fig. 207, and the tractor hydraulic-system schematic in Fig. 211.

Heavy agricultural equipment demands respect. Always practice safe shop protocols and consult a certified technician before starting a complex repair to prevent injury or equipment damage.

Examples of Clutch Pressures and Pump Test Data

For the covered Power Shift tractors, clutch operating pressure is specified at 180–200 psi with transmission fluid at operating temperature and the mechanical range transmission in neutral. Lubrication pressure is 55–65 psi with the inching pedal released.

The hydraulic flow tests specify normal operating temperature and 1,800 engine rpm. At 1,500 psi, minimum delivery is 6.3 gpm from the smaller pump section and 12.6 gpm from the larger section; their respective no-pressure test flows are 8 and 16 gpm.