This is the factory service manual for the Mustang AL 406 and AL506 articulated loaders, covering machines built with the Yanmar 4TNV88-BKGWL diesel engine across the AL 400 and AL 500 serial series. Published as part number 50940008, it runs 220 pages of repair-level detail.
Inside are full procedures for engine removal and installation, the hydrostatic drive and work hydraulics, front and rear axles, the cooling system, the machine and drive controllers with their error codes, and complete electrical schematics. Maintenance schedules, fluid capacities, and torque specifications are all included.
With this PDF you can diagnose a weak or erratic hydraulic circuit, pressure-test the drive and work systems, replace seals and filters to spec, and work through the diagnostic flow charts instead of guessing. It is the same information a dealer technician uses to service these loaders.
What's Inside This Manual
| System | Pages | Key Topics |
|---|---|---|
| Introduction | 7-8 | Safety Symbol, Signal Words, Contents and Use of this Manual, Machine Orientation, Service Parts |
| Safety | 9-16 | |
| Maintenance | 23-54 | Engine Air Cleaner, Engine Maintenance, Engine Oil, Maintenance Log, Maintenance Schedule, Check, Clean and Inspect, Functional Check |
| Operation | 55-66 | Operation Safety, Controls and Switches, Instrument Panel and Indicators |
| Chassis | 67-84 | Tilting the Platform, Lowering the Platform, Repairing or Replacing Platform Switch (Series: 41249 and Before, 51241 and Before), Hood Removal, Hood Installation |
| Engine | 85-94 | Engine Removal, Engine Installation, Drive Coupling Removal, Starter Removal |
| Cooling System | 95-100 | Radiator/Oil Cooler Removal, Radiator/Oil Cooler Installation |
| Axles | 101-108 | Front Axle Removal, Front Axle Installation, Rear Axle Removal, Rear Axle Installation |
| Hydraulics | 109-172 | Work Hydraulics Troubleshooting, Hydrostatic Drive System, Hydraulics Troubleshooting Diagnostic Flow Charts, Drive System Pressure Tests, Work System Pressure Tests |
| Machine/Drive Controllers | 173-188 | Machine and Drive Controllers, Machine Controller (Led/Indicator Assignments, Logic), Drive Controller (Error Codes) |
| Electrical System | 189-202 | Battery Removal, Battery Installation, Al 400 Series Complete Electrical Schematic, Al 400 Series Steering Column Electrical Schematic, Al 400 Series Chassis Electrical Schematic |
| Troubleshooting | 203-210 | Indicator Lamps / Seals and Hoses, Hydraulic System, Hydrostatic Drive System, Electrical |
| Torque Specifications | 215-219 | Hydraulic Fittings with Various Seals, With Coarse-Pitch Thread, With Fine-Pitch Thread |
| Back Cover | 220 | Mustang Manufacturing Co., Inc., P.O. Box 179, West Bend, 53095-0179 Usa, Www.Mustangmfg.Com |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Hydraulic fluid and return filter replacement interval | 500 Hours (or annually) | p. 25 |
| Hydraulic oil filter installation (gasket tightening) | 3/4 rotation past point where gasket contacts filter head | p. 35 |
| Hydraulic hose replacement action (damaged/leaking) | Repair/replace as required | p. 109 |
| Hydraulic fitting torque (M10X1.0, Sealing washer) | 7 lb-ft (9 Nm) | p. 215 |
| Hydraulic cylinder seals replacement action | Remove and discard, then install new seals | p. 149 |
| Teflon piston seals installation temperature | 130°-140° F (54°-60° C) | p. 147 |
| Fuel filter replacement interval | 500 Hours (or annually) | p. 25 |
| Fuel filter installation (gasket tightening) | 3/4 turn past point where gasket contacts filter head | p. 31 |
| Starter power rating | 12V - 2.3 kW | p. 21 |
| Starter mounting bolts torque | 64 lb-ft (87 N•m) | p. 94 |
| Gear/Work Hydraulic Pump mounting bolts torque | 33 lb-ft (45 N•m) | p. 155 |
| Piston/Drive Hydraulic Pump mounting bolts torque | 92 lb-ft (125 N•m) | p. 158 |
