1973–1979 John Deere JD301-A Tractor and Loader Technical Repair Manual (P/N TM-1088)

John Deere technical manual TM-1088 covers the JD301-A Tractor and Loader, including diesel and gasoline engine service, power train repair, hydraulics, and electrical diagnosis. The December 1978 cover is accompanied by revised pages dated through August 1979.

• Engine repair: Engine removal, cylinder-head and valve work, piston and wet-liner inspection, crankshaft service, and timing-gear installation.

• Fuel and cooling systems: Injection-pump removal and timing, fuel-system bleeding, carburetor and governor repair, plus radiator, water-pump, and thermostat service.

• Power train: Single- and dual-stage clutches, collar-shift transmission, reverser clutch and reverse brake repair, continuous-running and independent PTO systems, and planetary final drives.

• Hydraulics and steering: Transmission and main-pump overhaul, stroke-control adjustment, steering and loader valve repair, selective control valves, rockshaft adjustments, and hydraulic cylinder service.

• Electrical diagnosis: Alternator and starter testing, ignition service, gauge and switch checks, electrical schematics, and component wire-routing views.

• System testing: Engine troubleshooting charts, hydraulic analyzer tests, circuit- and cylinder-leakage checks, brake bleeding, and component-specific specifications and special-tool references.

Written for experienced service technicians, this manual assumes the shop knowledge and test equipment needed for component overhaul and hydraulic diagnosis.

Engine, Fuel, and Cooling Service

The cylinder-head, camshaft, piston, liner, crankshaft, and lubrication-system sections pair inspection limits with repair instructions. Timing-gear coverage distinguishes diesel and gasoline arrangements and identifies the JD-254 camshaft timing tool. The Cutaway View of Water Pump Assembly supports the cooling-system repair material.

Injection equipment: Roosa-Master fuel-system coverage includes pump removal, installation and timing, drive-shaft seal work, nozzle removal and installation, and bleeding. Detailed internal pump repair and nozzle testing refer to the separate SM-2045, which is not included in this download.

The injection-line instructions address sealing-washer selection because incorrect washers can allow the injection screws to bottom against the hydraulic head and cause pump seizure.

Clutches, Reverser, and Final Drives

Reverser overhaul covers the forward clutch pack, reverse brake, planetary gears, piston seals, and spring-washer arrangement. The Engine and PTO Clutch and Flywheel illustration identifies the continuous-running PTO assembly used without a reverser.

Engine installation: On continuous-PTO tractors, incorrect clutch-shaft indexing during engine installation can break the driven disk and pressure plate. The manual explains the engagement relationship between the transmission and PTO shafts.

Differential-lock service, ring-and-pinion tooth-pattern checks, parking-brake adjustments, and planetary final-drive repair are also included. Serial-specific illustrations distinguish changes to clutch controls, reverser linkage, and PTO brake components.

Hydraulic Diagnosis and Loader Components

Component sections include the reverser accumulator, transmission filter relief valve, oil cooler, auxiliary reservoir, steering valves, and loader controls. Rockshaft coverage includes load-control linkage and adjustment procedures; hydraulic wet-disk brake service includes bleeding and pedal adjustment.

The analyzer section connects its Symptom Index and Test Pattern Analysis Chart to dedicated pump, circuit-leakage, and cylinder-leakage tests. These references help distinguish restricted transmission supply from main-pump wear or internal high-pressure leakage before component overhaul.

The Hydraulic Schematic traces the connected circuits, while pressure-control valve illustrations distinguish the serial-specific versions.

Front end and loader structure: Separate material covers solid and adjustable front axles, loader frame, boom, bucket, and three-point hitch service. Because loader repairs involve heavy components and stored hydraulic pressure, follow the manual’s support, lifting, and pressure-relief precautions.

Electrical Testing and Wire Routing

Alternator diagnosis includes rotor, stator, and diode checks. Starting-system coverage includes solenoid tests, no-load testing, and pinion-clearance checks.

The Electrical Schematic and Component Wire Routing views identify circuit connections, terminal markings, and wire colors. Related test points support fault isolation in the starting, charging, ignition, lighting, and accessory circuits.

A Preview of Engine Capacity and Inspection Data

These examples represent a small selection of the engine service data in the manual. Engine lubrication capacity is 6 U.S. quarts including the filter, and the engine-to-clutch housing cap screw torque is 170 lb-ft.

For both diesel and gasoline engines, specified crankshaft end play is 0.0020–0.0080 in., with a maximum allowable end play of 0.0150 in. The inspection material distinguishes the specified range from the service limit.

Text Search, Bookmarks, and PDF Contents

Search and drawing detail: Most text pages have searchable OCR, but several color hydraulic and ignition illustrations lack searchable text. Embedded bookmarks cover the main sections and many service subsections. Small electrical and hydraulic schematic labels require zooming.

The download contains one printable, 492-page PDF. That total includes 10 opening pages of cover and preliminary material, 480 pages of technical sections and index, and two closing pages—one blank and one bearing a safety symbol. All of these pages are already included in the stated total.