260-SERIES ELECTROHYDRAULIC LIFT SERVICE MANUAL Table of Contents – Page 1 of 1 SAFETY INFORMATION LIFT SYSTEM COMPONENTS PUMP ASSEMBLY COMPONENTS 108 SERIES POWER UNIT COMPONENTS OPERATION PUMP/VALVE DESCRIPTION PUMP/VALVE COMPONENTS ADAPTER BLOCK COMPONENTS (AS VIEWED FROM MOTOR END) OIL FLOW AND CHECK VALVE OPERATION (AS VIEWED FROM MOTOR END) PUMP IN NEUTRAL MODE PUMP IN RAISE MODE PUMP IN LOWER MODE RELIEF VALVE TESTING (PUMP AS VIEWED FROM RESERVOIR END) UP MODE RELIEF VALVE REMOVAL/ADJUSTMENT PROCEDU
60-Series Electrohydraulic Lift
About This Manual This manual was written expressly for 260-Series Hydrostatic Tractors equipped with an electrohydraulic lift system. The Toro Company has made every effort to make the information in this manual complete and correct. This manual was written for the service technician; basic mechanical/electrical skills are assumed. The Contents page lists the systems and the related topics covered in this manual. We hope that you will find this manual a valuable addition to your service shop.
Contents Safety Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Lift System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pump Assembly Components . . . . . . . . . . . . . . . . . . . . . 108 Series Power Unit Components . . . . . . . . . . . Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pump/Valve Description . . . . . . . . . . . . . .
Safety Information This symbol means WARNING or PERSONAL SAFETY INSTRUCTION— read the instruction because it has to do with your safety. Failure to comply with the instruction may result in personal injury or even death. hydrostatic tractors. The tractor and attachment operator’s manuals contain safety information and operating tips for safe operating practices.
Lift System Components The electrohydraulic lift system consists of the following components: • Reservoir/Pump Assembly Oildyne 108 series Power Unit model 108AE19--AL--1HT • Control Switch and Wire Harness Hydraulic Fluid -- Dexron II or Dexron III 1 Capacity -- 12.5 oz. (.4 liter), not including hoses or cylinder. 1 3 2 Figure 1 1. Control switch and wire harness Figure 2 1. Filler plug/vent 2. Hose to rear of lift cylinder (Raise) Lift System 4 3.
• Hydraulic Cylinder, Hoses, and Linkage Figure 3 Electrohydraulic Lift System 5 Lift System
Pump Assembly Components 108 Series Power Unit Components Item Number Description Quantity 1 Motor Mounting Stud 2 2 Motor 1 3 Coupling 1 4 O ring 1 5 Adapter 1 6 ¼″ Steel Ball 3 7 Spool 1 8 Check Valve Body 2 9 Poppet Assembly 2 10 Spring 2 11 Hex Plug 2 12 3/16″ Ball 2 13 Eyelet 4 14 Spring 4 15 Thermal Relief 2 16 Shaft Seal 1 17 O ring 2 18 Pump 1 19 #10--32 UNF 1 5/16″ Torx Head Screw 2 20 Filter 2 21 Reservoir Seal 1 22 Reservoir 1 2
Operation Adapter Block Components (as viewed from motor end) When the top half of the control switch is depressed, the pump is activated, sending oil from the pump to the base end of the cylinder. This retracts the cylinder and raises the lift linkage. The adapter housing encloses the components shown in Fig. 6. When the bottom half of the control switch is depressed, the pump is activated, sending oil from the pump to the rod end of the cylinder. This extends the cylinder and lowers the lift linkage.
Pump in Raise Mode Pump in Lower Mode With the lift switch held in the “RAISE” position, oil is directed to the high-pressure side of the adapter housing. Hydraulic pressure moves the spool, which unseats the low-pressure check valve. Since the low pressure check valve is unseated, oil from the unpressurized end of the lift cylinder is free to return to the pump reservoir. With the lift switch held in the “LOWER” position, oil is directed to the low-pressure side of the adapter housing.
Inspect the relief valve ball and seat for any damage. Clean parts with solvent and then reassemble. Note: Ambient temperatures less than 70_F (39_C) may result in less pump flow. Replace the relief valve body into the housing using the same number of turns that were counted during removal. If test results show that less then 8 oz. (.
Lift Cylinder Servicing Grease the rod threads to protect the O rings and remove the piston and cylinder head from the rod. Description The lift cylinder is a double acting cylinder measuring 1″ (25.4mm) in diameter. It is serviceable with Seal Kit 94--9723. Rebuild Procedures Disassembly Figure 15 Clamp the cylinder in a vise. IMPORTANT: Use wood blocks to prevent damage to the cylinder tube. Remove the seals from the piston.
Reassembly Cylinder Head Lift System Electrical Components Insert the wiper seal, 1, into the cylinder head with seal lip facing outside (Fig. 17). The main components of the lift’s electrical system are listed below, along with their functions: Place the O ring, 2, on the outside diameter of the cylinder head. • 25 amp Fuse -- protects the system Install the backup washer, 3, into the groove, then insert the polypack seal, 4, into the groove.
Wiring Diagrams Lift Electrical System De-energized With the tractor key switch in the “OFF” position, voltage is present at the 25--amp fuse and terminal 30 of the relay. 1 2 3 5 4 + Figure 19 1. Pump motor 2. Hour meter 3. Main harness connection 4. Power lift relay 5.
Lift Electrical System Energized With the tractor key switch in the “RUN” position, the relay coil is energized (terminals 86/85), and terminals 30 and 87 are connected. Voltage is then present at terminals 1 and 6 of the lift switch. 1 2 3 5 4 + -- Figure 20 1. Pump motor 2. Hour meter 3. Main harness connection 4. Power lift relay 5.
Lift Switch Current Flow Up Position With the lift switch in the “UP position, current is transferred from terminal 6 to terminal 5. From terminal 5, current flows to the white/green wire connected to the electric motor of the hydraulic pump. The ground circuit is between terminals 3 and 2 and the orange wire connected to the electric motor of the hydraulic pump. 1 2 3 5 4 + -- Figure 21 1. Pump motor 2. Hour meter 3. Main harness connection 4. Power lift relay 5.
Down Position With the lift switch in the “DOWN” position, current is transferred from terminal 1 to terminal 2. From terminal 2, current flows to the orange wire connected to the electric motor of the hydraulic pump. The ground circuit is between terminals 4 and 5 and the white/green wire connected to the electric motor of the hydraulic pump. 1 2 3 5 4 + -- Figure 22 1. Pump motor 2. Hour meter 3. Main harness connection 4. Power lift relay 5.
