Minneapolis-Moline M-670 Tractor 1964–1970 Shop Manual (P/N S-450)

• 204-page PDF containing Minneapolis-Moline Shop Manual S-450, covering the M-670 and M-670 Super and incorporating factory M-670 Super material dated October 1, 1966.
• Separates Gasoline, LP-Gas, and Diesel service, including carburetor adjustment and overhaul, vaporizer-regulator testing and repair, Roosa-Master pump removal and timing, system bleeding, injection-nozzle testing, energy-cell service, and fuel-filter work.
• Takes engine repair through compression testing, cylinder-head and valve reconditioning, piston, ring, connecting-rod, crankshaft, and main-bearing service, camshaft timing, engine oil-pump overhaul, cooling-system work, and Pierce or Hoof governor adjustment.
• Covers Tel-O-Flo and Type E hydraulics with pressure and pump-performance tests, draft-control and dash-pot checks, valve-spool adjustment and synchronization, lift removal and repair, remote-cylinder operation, and a Tel-O-Flo troubleshooting chart.
• Distinguishes M-670 hydraulic steering and standard PTO/belt-pulley service from M-670 Super independent power steering and dual-speed PTO procedures, including bleeding, pump and hydramotor repair, clutch and brake adjustment, disassembly, inspection, and reassembly.
• Details the engine clutch, Ampli-Torc, sliding-gear transmission, differential and rear axles, brakes, Type E/U/N front-end components, wheel bearings, and tractor separation, backed by torque, clearance, preload, wear-limit, pressure-test, capacity, and electrical-test data.
• Visual references include power-steering neutral and turn oil-flow schematics, Tel-O-Flo raise/float/draft diagrams, Type E valve-flow views, the Ampli-Torc exploded view, and separate Diesel and Gasoline/LP-Gas wiring diagrams.

This shop manual was prepared by Minneapolis-Moline as a guide for MM dealers and their service personnel, covering work from minor tests and adjustments through complete overhaul. Its pressure and flow diagnosis, precision measurement, nozzle testing, press work, and tractor-splitting procedures make it best suited to experienced mechanics with a properly equipped shop.

Model and Configuration Coverage

The factory supplement makes the model split clear. The original hydraulic-steering and standard PTO/belt-pulley sections apply to the M-670; the M-670 Super uses Section 2A for its self-contained power-steering system and Section 16A for its 540/1000 RPM PTO. The manual also accounts for Tel-O-Flo versus Type E hydraulics, Pierce and Hoof governors, Type E/U/N front-end arrangements, early and later gasoline carburetors, early Tel-O-Flo lift components, and the later high-speed cooling fan. Fuel- and altitude-specific cylinder-head and ignition-timing charts identify the applicable head by part number.

Engine and Fuel-System Repair

The 336 cu. in. engine chapters provide specifications and repair procedures for all three fuel configurations. Coverage runs from compression diagnosis and head removal through guide and seat work, valve refacing, spring inspection, piston and ring fitting, connecting-rod alignment, cylinder reconditioning, bearing checks, crankshaft removal, timing-gear installation, and final ignition or injection timing.

Gasoline chapters distinguish fixed- and adjustable-load-jet carburetors. LP-Gas material covers the carburetor, vaporizer-regulator, strainers, leak checks, and final adjustments. Diesel procedures address the fuel filters, Roosa-Master pump removal, installation, timing, and bleeding, plus nozzle opening, leakage, dribble, and spray-pattern tests and energy-cell removal and installation. Internal overhaul of the sealed injection pump is outside the manual’s shop procedure; it directs that work to an authorized Roosa-Master service station.

Hydraulic and Drivetrain Shop Detail

Tel-O-Flo coverage explains three-point lift, traction amplification, temporary raise, rate-of-drop control, dash-pot operation, back-flow and relief valves, master and directional spools, auxiliary-valve synchronization, rockshaft service, and fault isolation. Type E coverage addresses single- and double-acting remote cylinders, kick-out operation, filtration, pressure checks, and valve adjustment. Section 11 adds hydraulic-pump flow diagnosis and gives dimensions and a component list for a pressure-test adapter when a flow meter is unavailable.

Factory tooling is identified where it matters: steering needle-bearing installer 10T5178, clutch bushing driver/alignment tool 10A12741, Ampli-Torc wrench 10A12802, transmission seal sleeve 10A12739, and bull-pinion seal sleeve 10P2644. The drivetrain chapters then carry repair work through clutch setup, Ampli-Torc teardown and adjustment, transmission-shaft and bearing preload, differential and final-drive service, PTO clutch work, brake repair, front-axle service, and separation at both major tractor joints.

Repair Cautions

The diesel chapter warns that the marks on the injection-pump mounting flange are calibration marks, not the installation-timing reference; attempting to time the pump with the engine running can seriously damage it. During engine-clutch repair, the pressure plate and back plate must retain their original relative positions because the clutch is balanced as an assembly. The Ampli-Torc cam-cage oil hole must face upward to maintain lubrication.

The covered work involves pressurized hydraulics, escaping LP-Gas, high-pressure diesel spray, heavy assemblies, and tractor separation. Use the supports, lifting equipment, pressure-relief steps, fuel-isolation measures, and protective precautions specified in the manual before beginning repair.