Allis Chalmers 616, 620, 720 Repair Manual — Wiring Diagrams

Within the hour you could have this Allis Chalmers 720 repair manual PDF open on the bench beside a dead hydrostat, all 129 pages of factory document TP 500-0504-01-PM-SA covering the 616, 620, and 720 tractors. Wiring diagrams trace each circuit from the battery through the charging, ignition, starting, and PTO switch checks, and hydraulic schematics map the power lift valve and cylinder. The in-line hydrostatic section takes the pump, motor, and center section apart and back together, closing with a priming procedure, an exploded view, and a test after repair. Check charge pump pressure at three quarter to full throttle against the 50 to 150 psi spec, then confirm the implement relief reads 550 to 800 psi. A guessed clearance costs you a second teardown. Bookmarked and text searchable, this PDF goes wherever the tractor quit, shed or field, so hay does not wait on a parts counter.

What's Inside This Repair Manual

Quick Reference Specifications