PW/PY PG/PE PR PJ/PK PC P Series Hydrostatic Pumps Service and Repair Manual BLN-52503 January, 2014
Table of Contents Section Page Description and Operation.................................................................................................. 1 Introduction................................................................................................................................................... 1 General Description...................................................................................................................................... 1 External Features.................
FOREWORD Headquartered in Sullivan, Illinois, Hydro-Gear is a world leader in the design, manufacture, and service of quality hydrostatic transaxles for the lawn and garden industry. The mission of our company is to be recognized by our customers and the industry as a world-class supplier and the quality leader in everything we do. This Service and Repair Manual is designed to provide information useful in servicing the Hydro-Gear 6cc (0.37 cu in.) PC Series, the 10 cc (0.61 cu in.) PG Series, the 12 cc (0.
SECTION 1. DESCRIPTION AND OPERATION INTRODUCTION The purpose of this manual is to provide information useful in servicing the Hydro-Gear PC, PG, PE PJ, PK, PR. PW and PY Pumps. This manual includes the pump’s general descriptions, hydraulic schematics, technical specifications, servicing and troubleshooting procedures for the pumps. The P Series Pumps normally will not require servicing during the life of the vehicle in which it is installed.
EXTERNAL FEATURES - PC SERIES Figure 1.
EXTERNAL FEATURES - PG / PE SERIES SAE “A” PAD FLANGE STYLE INLET CHARGE PRESSURE DIAGNOSTIC PORT INPUT SHAFT “A” and “B” PORTS STANDARD CHECK VALVE OR SCR CASE DRAIN OPTION CHARGE COVER STANDARD CHECK VALVE OR SCR BYPASS VALVE TRUNNION ARM CASE DRAIN OPTION Figure 2.
EXTERNAL FEATURES - PJ SERIES Figure 3.
EXTERNAL FEATURES - PK SERIES Figure 4.
EXTERNAL FEATURES - PR SERIES BYPASS VALVE SAE “A” PAD FLANGE STYLE TRUNNION ARM INPUT SHAFT INLET CHARGE PRESSURE DIAGNOSTIC PORT “A” and “B” PORTS SYSTEM CHECK VALVE OR SHOCK VALVE SYSTEM CHECK VALVE OR SHOCK VALVE CASE DRAIN BYPASS VALVE CHARGE COVER CASE DRAIN Figure 4.
EXTERNAL FEATURES - PW / PY SERIES SAE “B” PAD FLANGE STYLE TRUNNION ARM “A” and “B” PORTS INPUT SHAFT BYPASS VALVE STANDARD CHECK VALVE OR SHOCK VALVE CHARGE PRESSURE DIAGNOSTIC PORT CASE DRAIN CHARGE COVER STANDARD CHECK VALVE OR SHOCK VALVE Figure 5.
HYDRAULIC SCHEMATIC System Check & Relief Valve Options Orifice size Relief pressure (psi) Relief pressure (bar) No Bleed .024 Bleed .031 Bleed .044 Bleed Check ball 120 160 200 Check ball 1740 2320 2900 OR OR PORT “A” SYSTEM CHARGE RELIEF PORT “B” CHARGE PUMP INLET CHARGE DIAGNOSTIC BYPASS VALVE BLEED OPTIONS 1) NO BLEED ORIFICE 2) .031” BLEED ORIFICE Figure 6.
HYDRAULIC SCHEMATIC System Check & Relief Valve Options Orifice size Relief pressure (psi) Relief pressure (bar) No Bleed .024 Bleed .031 Bleed .044 Bleed Check ball 120 160 200 Check ball 1740 2320 2900 OR PORT “A” PORT “B” BYPASS VALVE BLEED OPTIONS 1) NO BLEED ORIFICE 2) .031” BLEED ORIFICE CHARGE DIAGNOSTIC CHARGE PUMP INLET Figure 8. PW / PY Series Pump With Standard Charge Pump System Check & Relief Valve Options Orifice size Relief pressure (psi) Relief pressure (bar) No Bleed .
GRAPHICAL SCHEMATIC Figure 10. P Series Pump With Standard Charge Pump Figures 10 represents a graphical schematic of the P Series Pump with standard charge pump. Figure 10 provides a graphical illustration of the hydraulic oil circuit. The input shaft and pump cylinder block are turned in one direction only by the engine/drive belt/pulley combination or direct drive gear box. The oil is drawn through an external filter by the charge pump.
TECHNICAL SPECIFICATIONS Product Type Displacement Input Speed in3/rev [cc/rev] PC PG/PE PJ/PK PR 0.37 [6.1] 0.62 [10.2] 0.73 [12] 0.97 [16] Maximum Unloaded RPM Minimum Loaded RPM System Operating Pressure Continuous Intermittent Peak Pump Performance @2400 rpm/1000 psi @3000 rpm/1000 psi @3600 rpm/1000 psi 750 [51] 1000 [75] 1250[86] psi [bar] 1750 [120] 2100 [145] 2500 [172] psi [bar] 2500 172] 3500 [240] 3750 [260] 3.6 [13.6] 4.5 [17.0] 5.4 [20.4] 6.1 [23.1] 7.6 [28.8] 9.2 [34.
PRODUCT IDENTIFICATION The label in Figure 11 is located on the pump housing. It identifies the model and configuration of the pump. HYDRO-GEAR Model Number PC-AGCC-MV1X-XXXX 4 244 P1 0192 MADE IN U.S.A. Year Built Date (Julian - day of year) Serial Number (unique number for that model - for that day) Type of Product and Build Information Figure 11.
SECTION 2. SAFETY This symbol points out important safety instructions which, if not followed, could endanger the personal safety and/or property of yourself and others. Read and follow all instructions in this manual before attempting maintenance on your P Series Pump. When you see this symbol - HEED ITS WARNING. Wear appropriate clothing. Loose or hanging clothing or jewelry can be hazardous. Use the appropriate safety equipment, such as eye and hearing protection, and safety-toe and slip-proof shoes.
SECTION 3. TROUBLESHOOTING WARNING Do not attempt any servicing or adjustments with the engine running. Use extreme caution while inspecting the drive belt assembly and all vehicle linkage! Follow all safety procedures outlined in the vehicle owner’s manual! In many cases, problems with the P Series Pump are not related to a defective pump but are caused by slipping drive belts, partially engaged bypass valves, and loose or damaged control linkages.
Possible Cause Corrective Action UNIT HAS NO/LOW POWER Engine speed low Adjust to correct rpm setting Control linkage bent, loose or out of adjustment Repair or replace vehicle linkage Drive belt slipping or pulley damaged Repair or replace drive belt or pulley Oil level low or contaminated oil Fill reservoir to proper level or change oil Excessive loading Reduce vehicle load Bypass loose Tighten pump bypass per External Maintenance step 9, page 17 Air trapped in
P-SERIES FLOW TEST KIT INSTRUCTIONS - BLN-51334 April 2011 (This Instruction Sheet supersedes all previous flow testing instruction) Description: P Series Flow Test Kit (Part Number 70661) (Part Number 70661 Supersedes Part Numbers 70511 and BB-76810) Purpose: The design purpose of the P Series Flow Test Kit is to allow the customer to isolate the pump from the wheel motor and determine if the pump is acceptable.
Note: Raising the system oil temperature will make a difference in the readings you receive. It has been determined that to complete this test accurately, the oil temperature must be near system operating temperatures. Suggested temperature range is 160°- 210°F (71.1° - 98.9°C). 8. On the PC, PG, PJ, PE, PK, PL, PR, PW and PY, tighten the flow meter restriction valve until the gauge reads 300 psi (21bar). Record the flow reading on the Bi-Directional Flow Meter. 9.
SECTION 4. SERVICE AND MAINTENANCE NOTE: Any servicing dealer attempting a warranty repair must have prior approval before conducting maintenance of a Hydro-Gear product, unless the servicing dealer is a current authorized Hydro-Gear Service Center. EXTERNAL MAINTENANCE Regular external maintenance of a P Series Pump should include the following: 1. Check the vehicle operator’s manual for the recommended load ratings. Insure the current application does not exceed load rating. 2.
FLUID VOLUME AND LEVEL Certain situations may require additional fluid to be added or even replaced. Refer to the vehicle manufacturer’s recommendations for the proper fill location and level. After maintenance or oil change, follow purging procedures below and check the fluid level once the unit has been operated for approximately 1 minute. FLUID CHANGE In the event of oil contamination or degradation, oil addition or change may alleviate certain performance problems.
RETURN TO NEUTRAL SETTING WARNING WARNING POTENTIAL FOR SERIOUS INJURY Do not attempt any servicing or adjustments with the engine running. Use extreme caution while inspecting the drive belt assembly and all vehicle linkage! Inattention to proper safety, operation, or maintenance procedures could result in personal injury, or damage to the equipment. Before servicing or repairing the P Series Pump, fully read and understand the safety precautions described in this manual.
REPAIR - PC SERIES PUMP Repair - PC Series Pump ..................................................................................................... 21-36 How to Use This Manual .............................................................................................................. 21 General Instructions .................................................................................................................... 21 Tools and Torques ............................................................
TOOLS AND TORQUES Miscellaneous 3/8-Inch Drive Ratchet and Sockets P Series Service & Repair Manual 7/16-inch Socket Torque Wrench 1/2-Inch Socket Scribe, Paint Pen, or Marker 11/16-Inch Socket Seal Hook with a Magnet 10-mm Socket Flat Blade Screwdriver Combination Wrenches Pliers 7/16 Inch Internal Snap Ring 1/2 Inch Allen Wrenches 11/16 Inch 1/8 inch 10 mm 1/4 inch Table 1.
PC SERIES PUMP REPAIR REMOVAL, INSPECTION AND/OR REPLACEMENT OF RETURN TO NEUTRAL ASSEMBLY Refer to Figure 1. Inspection Prior to disassembly, note the position of the scissor arm brackets and the tab on the outer control arm bracket. 1. With the arm control linkage removed, inspect the trunnion arm (37) and trunnion arm seal (49). 2. Disassembly Inspect bushing (101) and all other linkage parts for damage, corrosion or wear. CAUTION: The spring used on the return to neutral linkage is under tension.
REMOVAL, INSPECTION AND/OR REPLACEMENT OF CONTROL ARM REMOVAL, INSPECTION AND/OR REPLACEMENT OF FAN ASSEMBLY Refer to Figure 2. Refer to Figure 3. Disassembly Disassembly 1. Remove the nut (106), washer (104) and bushing (101). 1. Remove the fan shroud (210) from the mounting bracket (209) by carefully pushing down on the shroud tabs. 2. Remove the outer control arm bracket. 3. Remove bolt (103), washer (104) and the inner control arm bracket. 2. Remove the nut (106) and fan assembly (90). 3.
REMOVAL, INSPECTION AND/OR REPLACEMENT OF INPUT SHAFT SEAL REMOVAL, INSPECTION AND/OR REPLACEMENT OF TRUNNION ARM SEAL Refer to Figure 4. Refer to Figure 5. Disassembly Disassembly 1. Remove retaining ring (22) from housing. 1. Remove the RTN assembly or control arm. 2. Remove lip seal (20). Care must be taken to prevent damage to the housing bore, shaft sealing surface, or bearing. Once removed, the seal is not reusable. 2. Remove the retainer and lip seal (49) from the housing.
REMOVAL, INSPECTION AND/OR REPLACEMENT OF SHOCK VALVES REMOVAL, INSPECTION AND/OR REPLACEMENT OF THE BYPASS Refer to Figure 6. Refer to Figure 7. Perform disassembly, inspection and assembly on shock valve one side at a time. Some units vary in “A” side to “B” side configuration. Disassembly Disassembly 1. Remove the shock valve (42) with an 11/16-inch wrench. 1. Loosen the bypass valve (15) using a 7/16-inch wrench. 2. Remove the bypass (15) from the end cap. Inspection 2.
REMOVAL, INSPECTION AND ASSEMBLY OF THE STANDARD OR THRU SHAFT CHARGE PUMP NOTE: For thru shaft charge pump assembly, follow steps 1 thru 8. For standard charge pump, follow steps 3 thru 8. Refer to Figure 8. Assembly Disassembly 1. 1. Prior to removal of the charge pump cover, place a mark on the cover and end cap for alignment at assembly. 2. Press the shaft seal into the charge cover. Be careful not to damage the shaft seal or charge cover bore. 2.
REMOVAL, INSPECTION AND/OR REPLACEMENT OF AUXILIARY PUMP (IF EQUIPPED) 3. Inspect the filter cover assembly threads and filter for wear, damage or foreign material. Refer to Figure 9. 1. Install the check ball, spring, and cap as one assembly (45) into the auxiliary relief valve port. Tighten to the correct torque value. See page 22. Assembly Disassembly 1. Prior to removal of the auxiliary pump, place a mark on the auxiliary pump (6), charge pump (7) and end cap (2) for alignment at assembly. 2.
3. Replace the housing gasket (5) with a new gasket before assembly. REMOVAL, INSPECTION AND ASSEMBLY OF THE END CAP Assembly Refer to Figure 10. 1. Install housing gasket (5) into housing gasket seat of housing (1). Disassembly 1. Remove charge pump. (See page 27). 2. Using a 10 mm wrench, loosen the end cap bolts (4) evenly. 3. Hold the end cap (2) in place and remove the four end cap bolts (4). 4. Slowly remove the end cap (2). 5. Remove housing gasket (5). Inspection 2.
REMOVAL, INSPECTION AND ASSEMBLY OF THE CYLINDER BLOCK Refer to Figure 11. Disassembly 1. Remove charge pump. (See page 27). 2. Remove end cap. (See page 29). 3. Tilt the pump on its side and drain remaining oil. Lift out the cylinder block assembly (25). 2. Install piston seats into the end of the pistons. 3. Install springs into the pistons. 4. Install each piston, spring and seat assembly into the cylinder block.
REMOVAL, INSPECTION AND ASSEMBLY OF BLOCK SPRING AND THRUST BEARING REMOVAL, INSPECTION AND ASSEMBLY OF SWASHPLATE AND CRADLE BEARINGS Refer to Figure 12. Refer to Figure 13. Disassembly Disassembly 1. Remove the block spring (29). Remove the swashplate (32). 2. Remove the thrust bearing and races (34). Inspection Inspection 1. Inspect the running surface of the bearing pocket of swashplate (32) for damage, nicks or unusual wear patterns. The running surface may show evidence of minor abrasion.
REMOVAL, INSPECTION AND ASSEMBLY OF INPUT SHAFT Refer to Figure 14. Assembly NOTE: If trunnion arm is to be removed, do not assemble input shaft until the trunnion arm is installed. Disassembly NOTE: During installation, lightly lubricate all seals, O-rings and gaskets with clean petroleum jelly prior to assembly. Also, protect the inner diameter of seals by covering the shaft with plastic wrap. 1. Remove the retaining ring (22). 2. Remove the lip seal (20). 3. Remove the spacer (21). 3.
REMOVAL, INSPECTION AND INSTALLATION OF TRUNNION ARM Refer to Figure 15. Disassembly 1. Remove the slot guide (38). 2. Remove and discard the trunnion seal retainer and seal (49). 3. Remove the trunnion arm (37). Assembly 1. Install the trunnion arm (37) into the housing (1) bore. Rotate the trunnion arm to verify free movement. NOTE: During installation, lightly lubricate all seals, O-rings and gaskets with clean petroleum jelly prior to assembly.
34 Figure 16. PC Pump Kit Number BOXES INDICATE ITEMS INCLUDED IN KITS.
ITEM LIST - PC SERIES Part numbers are not provided in this manual. See CD (BLN-51427) for part numbers. No. Description No. Description 1 2 4 5 6 44 Charge Relief Valve Kit (1/4 in. Plastic Ball and 50654 Spring) Auxiliary Relief Valve Kit Trunnion Seal/Retainer Kit Filter Kit Plate, Adapter (Gear AA) Plug, 5/16 - 24 Plug Filter Cover Pin, Straight Headless Pin, Straight Headless Fan Kit Overhaul Seal Kit Spacer, Return Spring, Extension Screw, 5/16 x 0.875 in. (PATCH) Washer, 0.34 x 0.88 x 0.06 in.
36 PC Series
REPAIR - PG AND PE SERIES PUMP Repair - PG and PE Series Pump.......................................................................................... 37-54 How to Use This Manual..............................................................................................................37 General Instructions.....................................................................................................................37 Tools and Torques..............................................................
TOOLS AND TORQUES Miscellaneous 3/8-Inch Drive Ratchet and Sockets P Series Service & Repair Manual 1/2-inch Socket Torque Wrench 9/16-inch Socket Scribe, Paint Pen, or Marker 5/8-inch Socket Seal Hook with a Magnet 10-mm Socket Flat Blade Screwdriver Combination Wrenches Pliers 1/2 inch Internal Snap Ring 9/16 inch 5/8 inch Allen Wrenches 7/8 inch 5mm 10 mm 3/16 inch 1/4 inch Table 1.
PG AND PE SERIES PUMP REPAIR REMOVAL, INSPECTION AND/OR REPLACEMENT OF RETURN TO NEUTRAL ASSEMBLY Refer to Figure 1. Inspection Prior to disassembly, note the position of the scissor arm brackets and the tab on the outer control arm bracket. 1. With the arm control linkage removed, inspect the trunnion arm (37) and trunnion arm seal (49). Disassembly 2. Inspect scissor arm (99) and all other linkage parts for damage, corrosion or wear.
REMOVAL, INSPECTION AND/OR REPLACEMENT OF CONTROL ARM REMOVAL, INSPECTION AND/OR REPLACEMENT OF FAN ASSEMBLY Refer to Figure 2. Refer to Figure 3. Disassembly Disassembly 1. Remove the bolt (106), washer (104) and bushing (101). 1. Remove the fan shroud (210) from the mounting bracket (209) by carefully pushing down on the shroud tabs. 2. Remove the outer control arm bracket. 3. Remove bolt (103), washer (104) and the inner control arm bracket. 2. Remove the nut (106) and fan assembly (90). 3.
REMOVAL, INSPECTION AND/OR REPLACEMENT OF INPUT SHAFT SEAL REMOVAL, INSPECTION AND/OR REPLACEMENT OF TRUNNION ARM (CONTROL ARM) SEAL Refer to Figure 4. Refer to Figure 5. Disassembly Disassembly 1. Remove retaining ring (22) from housing. 1. Remove the retainer and lip seal (49) from the housing (1). Care must be taken to prevent damage to the housing trunnion bore, trunnion arm (37) and sealing surface. Once removed the retainer and lip seal is not reusable. 2. Remove lip seal (20).
REMOVAL, INSPECTION AND/OR REPLACEMENT OF CHECK VALVES Refer to Figure 6. Disassembly Perform disassembly, inspection and assembly on check valves one side at a time. Some units vary in “A” side to “B” side check configuration. 1. Remove the check valve (42) with an 1/4” allen wrench. 2. Remove the valve spring and poppet from the end cap (2). Inspection REMOVAL, INSPECTION AND/ OR REPLACEMENT OF SYSTEM CHECK RELIEFS (SCR’S) OR SHOCK VALVES Refer to Figure 7.
REMOVAL, INSPECTION AND /OR REPLACEMENT OF THE BYPASS Refer to Figure 8. Disassembly 1. Loosen the bypass valve (15) using a 5/8” wrench. 2. Remove the bypass (15) from the end cap (2). Inspection 1. Inspect the bypass O-rings and mating seats in the end cap (2) for damage or foreign materials. 2. If damaged or worn replace bypass (15) Assembly 1. Lay the pump on its side, so the bypass port is horizontal. 2. Insert the bypass (15) into the bypass port on the end cap (2). Tighten to the proper torque value.
Assembly REMOVAL, INSPECTION AND ASSEMBLY OF STANDARD OR THRU SHAFT CHARGE PUMP NOTE: For the Thru Shaft charge pump follow steps 1-8. For the Standard charge pump follow steps 3-8. Refer to Figure 9. Disassembly 1. Lubricate the new shaft seal with petroleum jelly. 1. Prior to removal of the charge pump cover, place a mark on the cover and end cap for alignment at assembly. 2. Press the shaft seal into the charge cover. Be careful not to damage the seal or charge cover bore. 2.
REMOVAL, INSPECTION AND/OR REPLACEMENT OF AUXILIARY PUMP (IF EQUIPPED) 3. Inspect the filter cover assembly threads and filter for wear, damage or foreign material. Refer to Figure 10. Disassembly 1. Install the check ball, spring, and cap as one assembly (45) into the auxiliary relief valve port. Tighten to the correct torque value. See page 38. Assembly 1. Prior to removal of the auxiliary pump, place a mark on the auxiliary pump, charge pump (7) and end cap (2) for alignment at assembly. 2.
NOTE: Grooving in the valve plate and or end cap, made evident when the surface is checked by dragging a fingernail across it, would be cause for replacement of the valve plate. REMOVAL, INSPECTION AND ASSEMBLY OF THE END CAP AND VALVE PLATE Refer to Figure 11a and 11b. Disassembly 3. Inspect and replace alignment pins (3) if bent or distorted. 1. Using a 10 mm wrench, loosen the end cap bolts (4) evenly. 4. Replace the housing gasket (5) with a new gasket before reassembly. 2.
REMOVAL, INSPECTION AND ASSEMBLY OF THE CYLINDER BLOCK Refer to Figure 12. Assembly 1. Install piston seats into the end of the pistons. 2. Install springs into the pistons. 3. Install one at a time, pistons, springs and seats as one assembly into the cylinder block. Disassembly 1. Tilt the pump on its side, drain remaining oil. Lift out the cylinder block assembly (25). 2. Remove the pistons, springs and piston seats. Inspection 1.
REMOVAL, INSPECTION AND ASSEMBLY OF BLOCK SPRING, THRUST WASHER, AND THRUST BEARING Refer to Figure 13. REMOVAL, INSPECTION OF SWASHPLATE, INSPECTION OF CRADLE BEARINGS Refer to Figure 14. Disassembly Disassembly 1. Remove the block spring (29). 2. Remove the block thrust washer (30). 3. Remove the thrust bearing and race (34). Inspection 1. Inspect and replace the block spring (29) and thrust washer (30) if they are distorted or broken. 2.
REMOVAL, INSPECTION AND ASSEMBLY OF INPUT SHAFT NOTE: If trunnion arm is to be removed, delay reassembly of input shaft assembly. Refer to Figure 15. Assembly Disassembly NOTE: Upon removal, it is recommended that all seals, O-rings and gaskets be replaced. During installation, lightly lubricate all seals, O-rings and gaskets with clean petroleum jelly prior to assembly. Also, protect the inner diameter of seals by covering the shaft with plastic wrap. 1. Remove the retaining ring (22). 2.
REMOVAL AND INSPECTION OF TRUNNION ARM Refer to Figure 16. 1 Disassembly 1. Remove the slot guide (38). 2. Remove and discard the trunnion seal retainer and seal (49). 3. Remove the trunnion arm (37). Inspection 1. Inspect the trunnion arm (37) for wear or damage. Replace the trunnion arm if necessary. Assembly 38 37 49 Figure 16. PG / PE Pump Trunnion Arm 1. Install the trunnion arm (37) into the housing (1) bore. Rotate the trunnion arm to verify free movement.
PG / PE Series 51
Figure 17. PG / PE Pump 52 PG / PE Series BOXES INDICATE ITEMS INCLUDED IN KITS.
ITEM LIST - PG AND PE SERIES Part numbers are not provided in this manual. See CD (BLN-51427) for part numbers. No.
54 PG / PE Series
REPAIR - PJ SERIES PUMP Repair - PJ Series Pump ...................................................................................................... 55-72 How to Use This Manual .............................................................................................................. 55 General Instructions .................................................................................................................... 55 Tools and Torques ...........................................................
TOOLS AND TORQUES Miscellaneous 3/8-Inch Drive Ratchet and Sockets P Series Service & Repair Manual 7/16-inch Socket Torque Wrench 1/2-inch Socket Scribe, Paint Pen, or Marker 9/16-inch Socket Seal Hook with a Magnet 5/8-inch Socket Flat Blade Screwdriver 11/16-inch Socket 10-mm Socket Pliers Combination Wrenches Internal Snap Ring 7/16 inch Allen Wrenches 1/2 inch 5mm 9/16 inch 1/8 inch 5/8 inch 3/16 inch 11/16 inch 1/4 inch 7/8 inch 10 mm Table 1.
PJ SERIES PUMP REPAIR REMOVAL, INSPECTION AND/OR REPLACEMENT OF RETURN TO NEUTRAL ASSEMBLY Refer to Figure 1. Inspection Prior to disassembly, note the position of the scissor arm brackets and the tab on the outer control arm bracket. 1. With the arm control linkage removed, inspect the trunnion arm (37) and trunnion arm seal (49). Disassembly 2. Inspect scissor arm (99) and all other linkage parts for damage, corrosion or wear.
REMOVAL, INSPECTION AND/OR REPLACEMENT OF CONTROL ARM REMOVAL, INSPECTION AND/OR REPLACEMENT OF FAN ASSEMBLY Refer to Figure 2. Refer to Figure 3. Disassembly Disassembly 1. Remove the bolt (106)/nut (107), washer (104) and bushing (101). 1. Remove the fan shroud (210) from the mounting bracket (209) by carefully pushing down on the shroud tabs. 2. Remove the outer control arm bracket. 3. Remove bolt (103), washer (104) and the inner control arm bracket. 2.
REMOVAL, INSPECTION AND/OR REPLACEMENT OF INPUT SHAFT SEAL REMOVAL, INSPECTION AND/OR REPLACEMENT OF TRUNNION ARM SEAL Refer to Figure 4. Refer to Figure 5. Disassembly Disassembly 1. Remove retaining ring (22) from housing. 1. Remove the RTN assembly or control arm. 2. Remove lip seal (20). Care must be taken to prevent damage to the housing bore, shaft sealing surface, or bearing. Once removed, the seal is not reusable. 2. Remove the retainer and lip seal (49) from the housing.
REMOVAL, INSPECTION AND/OR REPLACEMENT OF CHECK VALVES Refer to Figure 6. Perform disassembly, inspection and assembly on check valves one side at a time. Some units vary in “A” side to “B” side check configuration. REMOVAL, INSPECTION AND/OR REPLACEMENT OF SYSTEM CHECK RELIEFS (SCR’S) OR SHOCK VALVES Refer to Figure 7. Disassembly Disassembly 1. Remove the check valve (42) with an 1/4” allen wrench. Perform disassembly, inspection and assembly on SCR/shock valve one side at a time.
REMOVAL, INSPECTION AND /OR REPLACEMENT OF THE BYPASS Refer to Figure 8. Disassembly 1. Loosen the bypass valve (15) using a 5/8” wrench. 2. Remove the bypass (15) from the end cap (2). Inspection 1. Inspect the bypass O-rings and mating seats in the end cap (2) for damage or foreign materials. 2. If damaged or worn replace bypass (15) Assembly 1. Lay the pump on its side, so the bypass port is horizontal. 2. Insert the bypass (15) into the bypass port on the end cap (2). Tighten to the proper torque value.
Assembly REMOVAL, INSPECTION AND ASSEMBLY OF STANDARD OR THRU SHAFT CHARGE PUMP NOTE: For the Thru Shaft charge pump follow steps 1-8. For the Standard charge pump follow steps 3-8. Refer to Figure 9. 1. Lubricate the new shaft seal with petroleum jelly. Disassembly 1. Prior to removal of the charge pump cover, place a mark on the cover and end cap for alignment at assembly. 2. Using a 1/2 inch wrench, or 5 mm allen wrench, loosen the charge pump cover bolts (10) from the end cap (2).
REMOVAL, INSPECTION AND/OR REPLACEMENT OF AUXILIARY PUMP (IF EQUIPPED) 3. Inspect the filter cover assembly threads and filter for wear, damage or foreign material. Refer to Figure 10. 1. Install the check ball, spring, and cap as one assembly (45) into the auxiliary relief valve port. Tighten to the correct torque value. See page 56. Disassembly 1. Prior to removal of the auxiliary pump, place a mark on the auxiliary pump, charge pump (7) and end cap (2) for alignment at assembly. 2.
REMOVAL, INSPECTION AND ASSEMBLY OF THE END CAP 3. Replace the housing gasket (5) with a new gasket before assembly. Assembly Refer to Figure 11. 1. Install housing gasket (5) into gasket seat of housing (1). Disassembly 1. Remove charge pump. (See page 62). 2. Using a 10 mm wrench, loosen the end cap bolts (4) evenly. 2. Lubricate the cylinder block (25) to end cap (2) mating surface with clean oil prior to installation. 5. Remove housing gasket (5). 3. Install end cap (2).
REMOVAL, INSPECTION AND ASSEMBLY OF THE CYLINDER BLOCK Refer to Figure 12. Disassembly 1. Remove charge pump. (See page 62). 2. Remove end cap. (See page 64). 3. Tilt the pump on its side and drain remaining oil. Lift out the cylinder block assembly (25). 4. Remove the pistons, springs and piston seats. Inspection 1. Inspect the running surface of the cylinder block and piston ends for damage, nicks or unusual wear patterns. The running surface may show evidence of minor abrasion. This will be normal wear.
REMOVAL, INSPECTION AND ASSEMBLY OF BLOCK SPRING AND THRUST BEARING REMOVAL, INSPECTION AND ASSEMBLY OF SWASHPLATE AND CRADLE BEARINGS Refer to Figure 13. Refer to Figure 14. Disassembly Disassembly 1. Remove the block spring (29). 1. Remove the swashplate (32). 2. Remove the block thrust washer (30) and thrust bearing (34). Inspection Inspection 1. Inspect and replace the block spring (29) if it is distorted or broken. 2.
Assembly REMOVAL, INSPECTION AND ASSEMBLY OF INPUT SHAFT NOTE: If trunnion arm is to be removed, do not assemble input shaft until the trunnion arm is installed. Refer to Figure 15. Disassembly 1. Remove the retaining ring (22). 2. Remove the lip seal (20). 3. Remove the spacer (21). 4. Remove the shaft (18) and bearing (19) assembly from the pump. Inspection 1. Inspect the input shaft (18) for worn splines, surface damage, or keyway damage. Replace shaft assembly if necessary. 2.
REMOVAL, INSPECTION AND INSTALLATION OF TRUNNION ARM Refer to Figure 16. Disassembly 1. Remove the slot guide (38). 2. Remove and discard the trunnion seal retainer and seal (49). 3. Remove the trunnion arm (37). Inspection 1. Inspect the trunnion arm (37) for wear or damage. Replace the trunnion arm if necessary. 2. Check for excessive play between trunnion arm (37) and housing (1). Replace housing if necessary. Assembly 1. Install the trunnion arm (37) into the housing (1) bore.
PJ Series 69
Figure 17. PJ Pump 70 PJ Series BOXES INDICATE ITEMS INCLUDED IN KITS.
ITEM LIST - PJ SERIES Part numbers are not provided in this manual. See CD (BLN-51427) for part numbers. No.
72 PJ Series
REPAIR - PK SERIES PUMP Repair - PK Series Pump ...................................................................................................... 73-90 How to Use This Manual .............................................................................................................. 73 General Instructions .................................................................................................................... 73 Tools and Torques ...........................................................
TOOLS AND TORQUES Miscellaneous 3/8-Inch Drive Ratchet and Sockets P Series Service & Repair Manual 7/16-inch Socket Torque Wrench 1/2-inch Socket Scribe, Paint Pen, or Marker 9/16-inch Socket Seal Hook with a Magnet 5/8-inch Socket Flat Blade Screwdriver 11/16-inch Socket 10-mm Socket Pliers Combination Wrenches Internal Snap Ring 7/16 inch Allen Wrenches 1/2 inch 5mm 9/16 inch 1/8 inch 5/8 inch 3/16 inch 11/16 inch 1/4 inch 7/8 inch 10 mm Table 1.
PK SERIES PUMP REPAIR REMOVAL, INSPECTION AND/OR REPLACEMENT OF RETURN TO NEUTRAL ASSEMBLY Refer to Figure 1. Inspection Prior to disassembly, note the position of the scissor arm brackets and the tab on the outer control arm bracket. 1. With the arm control linkage removed, inspect the trunnion arm (37) and trunnion arm seal (49). Disassembly 2. Inspect scissor arm (99) and all other linkage parts for damage, corrosion or wear.
REMOVAL, INSPECTION AND/OR REPLACEMENT OF CONTROL ARM REMOVAL, INSPECTION AND/OR REPLACEMENT OF FAN ASSEMBLY Refer to Figure 2. Refer to Figure 3. Disassembly Disassembly 1. Remove the bolt (106), washer (104) and bushing (101). 1. Remove the fan shroud (210) from the mounting bracket (209) by carefully pushing down on the shroud tabs. 2. Remove the outer control arm bracket. 3. Remove bolt (103), washer (104) and the inner control arm bracket. 2. Remove the nut (106) and fan assembly (90). 3.
REMOVAL, INSPECTION AND/OR REPLACEMENT OF INPUT SHAFT SEAL REMOVAL, INSPECTION AND/OR REPLACEMENT OF TRUNNION ARM SEAL Refer to Figure 4. Refer to Figure 5. Disassembly Disassembly 1. Remove retaining ring (22) from housing. 1. Remove the RTN assembly or control arm. 2. Remove lip seal (20). Care must be taken to prevent damage to the housing bore, shaft sealing surface, or bearing. Once removed, the seal is not reusable. 2. Remove the retainer and lip seal (49) from the housing.
REMOVAL, INSPECTION AND/OR REPLACEMENT OF CHECK VALVES Refer to Figure 6. Perform disassembly, inspection and assembly on check valves one side at a time. Some units vary in “A” side to “B” side check configuration. REMOVAL, INSPECTION AND/OR REPLACEMENT OF SYSTEM CHECK RELIEFS (SCR’S) OR SHOCK VALVES Refer to Figure 7. Disassembly Disassembly 1. Remove the check valve (42) with an 1/4” allen wrench. Perform disassembly, inspection and assembly on SCR/shock valve one side at a time.
REMOVAL, INSPECTION AND /OR REPLACEMENT OF THE BYPASS Refer to Figure 8. Disassembly 1. Loosen the bypass valve (15) using a 5/8” wrench. 2. Remove the bypass (15) from the end cap (2). Inspection 1. Inspect the bypass O-rings and mating seats in the end cap (2) for damage or foreign materials. 2. If damaged or worn replace bypass (15) Assembly 1. Lay the pump on its side, so the bypass port is horizontal. 2. Insert the bypass (15) into the bypass port on the end cap (2). Tighten to the proper torque value.
Assembly REMOVAL, INSPECTION AND ASSEMBLY OF STANDARD OR THRU SHAFT CHARGE PUMP NOTE: For the Thru Shaft charge pump follow steps 1-8. For the Standard charge pump follow steps 3-8. Refer to Figure 9. 1. Lubricate the new shaft seal with petroleum jelly. Disassembly 1. Prior to removal of the charge pump cover, place a mark on the cover and end cap for alignment at assembly. 2. Using a 1/2 inch wrench, or 5 mm allen wrench, loosen the charge pump cover bolts (10) from the end cap (2).
REMOVAL, INSPECTION AND/OR REPLACEMENT OF AUXILIARY PUMP (IF EQUIPPED) 3. Inspect the filter cover assembly threads and filter for wear, damage or foreign material. Refer to Figure 10. 1. Install the check ball, spring, and cap as one assembly (45) into the auxiliary relief valve port. Tighten to the correct torque value. See page 74. Disassembly 1. Prior to removal of the auxiliary pump, place a mark on the auxiliary pump, charge pump (7) and end cap (2) for alignment at assembly. 2.
REMOVAL, INSPECTION AND ASSEMBLY OF THE END CAP 3. Replace the housing gasket (5) with a new gasket before assembly. Assembly Refer to Figure 11. 1. Install housing gasket (5) into gasket seat of housing (1). Disassembly 1. Remove charge pump. (See page 62). 2. Using a 10 mm wrench, loosen the end cap bolts (4) evenly. 2. Lubricate the cylinder block (25) to end cap (2) mating surface with clean oil prior to installation. 5. Remove housing gasket (5). 3. Install end cap (2).
REMOVAL, INSPECTION AND ASSEMBLY OF THE CYLINDER BLOCK Refer to Figure 12. Disassembly 1. Remove charge pump. (See page 80. 2. Remove end cap. (See page 82). 3. Tilt the pump on its side and drain remaining oil. Lift out the cylinder block assembly (25). 4. Remove the pistons, springs and piston seats. Inspection 1. Inspect the running surface of the cylinder block and piston ends for damage, nicks or unusual wear patterns. The running surface may show evidence of minor abrasion. This will be normal wear.
REMOVAL, INSPECTION AND ASSEMBLY OF BLOCK SPRING AND THRUST BEARING REMOVAL, INSPECTION AND ASSEMBLY OF SWASHPLATE AND CRADLE BEARINGS Refer to Figure 13. Refer to Figure 14. Disassembly Disassembly 1. Remove the block spring (29). 1. Remove the swashplate (32). 2. Remove the block thrust washer (30) and thrust bearing (34). Inspection Inspection 1. Inspect and replace the block spring (29) if it is distorted or broken. 2.
Assembly REMOVAL, INSPECTION AND ASSEMBLY OF INPUT SHAFT NOTE: If trunnion arm is to be removed, do not assemble input shaft until the trunnion arm is installed. Refer to Figure 15. Disassembly 1. Remove the retaining ring (22). 2. Remove the lip seal (20). 3. Remove the spacer (21). 4. Remove the shaft (18) and bearing (19) assembly from the pump. Inspection 1. Inspect the input shaft (18) for worn splines, surface damage, or keyway damage. Replace shaft assembly if necessary. 2.
REMOVAL, INSPECTION AND INSTALLATION OF TRUNNION ARM Refer to Figure 16. Disassembly 1. Remove the slot guide (38). 2. Remove and discard the trunnion seal retainer and seal (49). 3. Remove the trunnion arm (37). Inspection 1. Inspect the trunnion arm (37) for wear or damage. Replace the trunnion arm if necessary. 2. Check for excessive play between trunnion arm (37) and housing (1). Replace housing if necessary. Assembly 1. Install the trunnion arm (37) into the housing (1) bore.
PK Series 87
Figure 17. PK Pump 88 PK Series BOXES INDICATE ITEMS INCLUDED IN KITS.
ITEM LIST - PK SERIES Part numbers are not provided in this manual. See website for part numbers. No.
90 PK Series
REPAIR - PR SERIES PUMP Repair - PR Series Pump..................................................................................................... 91-108 How to Use This Manual..............................................................................................................91 General Instructions.....................................................................................................................91 Tools and Torques................................................................
TOOLS AND TORQUES Miscellaneous 3/8-Inch Drive Ratchet and Sockets P Series Service & Repair Manual 1/2-inch Socket Torque Wrench 9/16-inch Socket Scribe, Paint Pen, or Marker 5/8-inch Socket Seal Hook with a Magnet 10-mm Socket Flat Blade Screwdriver Combination Wrenches Pliers 1/2 inch Internal Snap Ring 9/16 inch 5/8 inch Allen Wrenches 7/8 inch 5mm 10 mm 3/16 inch 1/4 inch Table 1.
PR SERIES PUMP REPAIR REMOVAL, INSPECTION AND/OR REPLACEMENT OF RETURN TO NEUTRAL ASSEMBLY Prior to disassembly, note the position of the scissor arm brackets and the tab on the outer control arm bracket. Inspection 1. With the arm control linkage removed, inspect the trunnion arm (13) and trunnion arm seal (12). See Figure 1. Disassembly 2. Inspect bushing (106) and all other linkage parts for damage, corrosion or wear. CAUTION: The spring used on the return to neutral linkage is under tension.
REMOVAL, INSPECTION AND/OR REPLACEMENT OF CONTROL ARM REMOVAL, INSPECTION AND/OR REPLACEMENT OF FAN ASSEMBLY Refer to Figure 2. Refer to Figure 3. Disassembly Disassembly 1. Remove the bolt (102), washer (99) and bushing (106). 1. Remove the fan shroud (210) from the mounting bracket (209) by carefully pushing down on the shroud tabs. 2. Remove the outer control arm bracket (101). 3. Remove bolt (107), washer (99) and the inner control arm bracket (105). 2. Remove the fan nut and fan assembly (90).
REMOVAL, INSPECTION AND/OR REPLACEMENT OF INPUT SHAFT SEAL Refer to Figure 4. REMOVAL, INSPECTION AND/OR REPLACEMENT OF TRUNNION ARM (CONTROL ARM) SEAL Refer to Figure 5. Disassembly Disassembly 1. Remove retaining ring (3) from housing (15). 2. Remove lip seal (6). Care must be taken to prevent damage to the housing bore, shaft sealing surface, or bearing. Once removed, the seal is not reusable. Inspection 1. Remove the retainer and lip seal (12) from the housing (15).
REMOVAL, INSPECTION AND/OR REPLACEMENT OF CHECK VALVES Refer to Figure 6. Disassembly REMOVAL, INSPECTION AND/ OR REPLACEMENT OF SYSTEM CHECK RELIEFS (SCR’S) OR SHOCK VALVES Perform disassembly, inspection and assembly on check valves one side at a time. Some units vary in “A” side to “B” side check configuration. Refer to Figure 7. 1. Remove the check valve (42) with an 1/4” allen wrench. Perform disassembly, inspection and assembly on SCR/shock valve one side at a time.
REMOVAL, INSPECTION AND /OR REPLACEMENT OF THE BYPASS Refer to Figure 8. Disassembly 1. Loosen the bypass valve (50) using a 5/8” wrench. 2. Remove the bypass (50) from the end cap (25). Inspection 1. Inspect the bypass O-rings and mating seats in the end cap (25) for damage or foreign materials. 2. If damaged or worn replace bypass (50). Assembly 1. Lay the pump on its side, so the bypass port is horizontal. 2. Insert the bypass (50) into the bypass port on the end cap (25).
REMOVAL, INSPECTION AND ASSEMBLY OF STANDARD OR THRU SHAFT CHARGE PUMP Assembly Disassembly 1. Lubricate the new shaft seal with petroleum jelly. NOTE: For the Thru Shaft charge pump follow steps 1-8. For the Standard charge pump follow steps 3-8. Refer to Figure 9. 1. Prior to removal of the charge pump cover, place a mark on the cover and end cap for alignment at assembly. 2. Using a 1/2 inch wrench loosen the charge pump cover bolts (56) from the end cap (2).
REMOVAL, INSPECTION AND/OR REPLACEMENT OF AUXILIARY PUMP (IF EQUIPPED) 2. Inspect all O-rings, gasket and mounting seats. 3. Inspect the filter cover assembly threads and filter for wear, damage or foreign material. Refer to Figure 10. Assembly Disassembly 1. Install the check ball, spring, and cap as one assembly (45) into the auxiliary relief valve port. Tighten to the correct torque value. See page 92. 1.
NOTE: Grooving in the valve plate and/or end cap, made evident when the surface is checked by dragging a fingernail across it, would be cause for replacement of the valve plate. REMOVAL, INSPECTION AND ASSEMBLY OF THE END CAP AND VALVE PLATE 3. Inspect and replace alignment pins (26) if bent or distorted. Refer to Figure 11. Disassembly 1. Using any combination of two, 9/16” wrenches or 9/16” socket and ratchet drive, loosen the end cap bolts (58) evenly. 4.
REMOVAL, INSPECTION AND ASSEMBLY OF THE CYLINDER BLOCK Assembly Refer to Figure 12. 3. Install one at a time, pistons, springs and seats as one assembly into the cylinder block. Disassembly 1. Tilt the pump on its side, drain remaining oil. Lift out the cylinder block assembly (38). 1. Install piston seats into the end of the pistons. 2. Install springs into the pistons. 4. With the pump housing tilted on its side, install the cylinder block assembly (38) with pistons contacting the thrust bearing.
REMOVAL, INSPECTION AND ASSEMBLY OF BLOCK SPRING, THRUST WASHER, AND THRUST BEARING Refer to Figure 14. Refer to Figure 13. Disassembly Disassembly 1. Remove the swashplate (31). 1. Remove the block spring (20). Inspection 2. Remove the thrust washer (19). 1. Inspect the running surface of the bearing pocket for damage (31), nicks or unusual wear patterns. The running surface may show evidence of minor abrasion. This is normal wear. Inspect the cradle bearing side of the swashplate (31) for damage.
REMOVAL, INSPECTION AND ASSEMBLY OF INPUT SHAFT NOTE: If trunnion arm is to be removed, delay reassembly of input shaft assembly. Refer to Figure 15. 5. Inspect and replace the thrust spring (20) and thrust washer (19) if they are distorted or broken. Assembly Disassembly 1. Remove the retaining ring (3). 2. Remove the lip seal (6). NOTE: Upon removal, it is recommended that all seals, O-rings and gaskets be replaced.
REMOVAL AND INSPECTION OF TRUNNION ARM Refer to Figure 16. Disassembly 1. Remove and discard the trunnion seal retainer and seal (12). 2. Remove the slot guide (14). NOTE: Upon removal, it is recommended that all seals, O-rings, and gaskets be replaced. During installation, lightly lubricate all seals, O-rings and gaskets with clean petroleum jelly prior to assembly. Also protect the inner diameter of seals by covering the shaft with plastic wrap. Remove the plastic wrap after the seal is installed. 3.
PR Series 105
Figure 17. PR Pump 106 PR Series BOXES INDICATE ITEMS INCLUDED IN KITS.
ITEM LIST - PR SERIES Part numbers are not provided in this manual. See CD (BLN-51427) for part numbers. No.
108 PR Series
REPAIR - PW / PY SERIES PUMP Repair - PW / PY Series Pump........................................................................................... 109-126 How to Use This Manual............................................................................................................109 General Instructions...................................................................................................................109 Tools and Torques.................................................................
TOOLS AND TORQUES Miscellaneous 3/8-Inch Drive Ratchet and Sockets P Series Service & Repair Manual 1/2-inch Socket Torque Wrench 9/16-inch Socket Scribe, Paint Pen, or Marker 5/8-inch Socket Seal Hook with a Magnet 10-mm Socket Flat Blade Screwdriver Combination Wrenches Pliers 1/2 inch Internal Snap Ring 9/16 inch 5/8 inch Allen Wrenches 7/8 inch 5mm 10 mm 3/16 inch 1/4 inch Table 1.
PW / PY SERIES PUMP REPAIR REMOVAL, INSPECTION AND/OR REPLACEMENT OF RETURN TO NEUTRAL ASSEMBLY Prior to disassembly, note the position of the scissor arm brackets and the tab on the outer control arm bracket. See Figure 1. Inspection 1. With the arm control linkage removed, inspect the trunnion arm and trunnion arm seal. 2. Inspect bushing (116) and all other linkage parts for damage, corrosion or wear. Disassembly CAUTION: The spring used on the return to neutral linkage is under tension.
REMOVAL, INSPECTION AND/OR REPLACEMENT OF CONTROL ARM REMOVAL, INSPECTION AND/OR REPLACEMENT OF FAN ASSEMBLY Refer to Figure 2. Refer to Figure 3. Disassembly Disassembly 1. Remove the bolt (112), washer (109) and bushing (116). 1. Remove the fan shroud (210) from the mounting bracket (209) by carefully pushing down on the shroud tabs. 2. Remove the outer control arm bracket (111). 3. Remove bolt (117), washer (109) and the inner control arm bracket (115). 2.
REMOVAL, INSPECTION AND/OR REPLACEMENT OF INPUT SHAFT SEAL REMOVAL, INSPECTION AND/OR REPLACEMENT OF TRUNNION ARM (CONTROL ARM) SEAL Refer to Figure 4. Refer to Figure 5. Disassembly Disassembly 1. Remove retaining ring (3) from housing (15). 1. Remove the retainer and lip seal (12). Care must be taken to prevent damage to the housing trunnion bore, trunnion arm (13) and sealing surface. Once removed the retainer and lip seal (12) is not reusable. 2. Remove lip seal (6).
REMOVAL, INSPECTION AND/OR REPLACEMENT OF CHECK VALVES Refer to Figure 6. Disassembly REMOVAL, INSPECTION AND/ OR REPLACEMENT OF SYSTEM CHECK RELIEFS (SCR’S) OR SHOCK VALVES Perform disassembly, inspection and assembly on check valves one side at a time. Some units vary in “A” side to “B” side check configuration. Refer to Figure 7. 1. Remove the check valve (42) with an 1/4” allen wrench. Perform disassembly, inspection and assembly on SCR/shock valve one side at a time.
REMOVAL, INSPECTION AND /OR REPLACEMENT OF THE BYPASS Refer to Figure 8. Disassembly 1. Loosen the bypass valve (50) using a 5/8” wrench. 2. Remove the bypass (50) from the end cap (25). Inspection 1. Inspect the bypass O-rings and mating seats in the end cap (25) for damage or foreign materials. 2. If damaged or worn replace bypass (50) Assembly 1. Lay the pump on its side, so the bypass port is horizontal. 2. Insert the bypass (50) into the bypass port on the end cap (25).
Assembly REMOVAL, INSPECTION AND ASSEMBLY OF STANDARD OR THRU SHAFT CHARGE PUMP For the Thru Shaft charge pump follow steps 1-8. For the Standard charge pump follow steps 3-8. Refer to Figure 9. 1. Lubricate the new shaft seal with petroleum jelly. Disassembly 1. Prior to removal of the charge pump cover, place a mark on the cover and end cap for alignment at assembly. 2. Using a 1/2 inch wrench loosen the charge pump cover bolts (56) from the end cap (25).
REMOVAL, INSPECTION AND/OR REPLACEMENT OF AUXILIARY PUMP (IF EQUIPPED) 2. Inspect all O-rings, gasket and mounting seats. 3. Inspect the filter cover assembly threads and filter for wear, damage or foreign material. Refer to Figure 10. Assembly Disassembly 1. Install the check ball, spring, and cap as one assembly (45) into the auxiliary relief valve port. Tighten to the correct torque value. See page 110. 1.
REMOVAL, INSPECTION AND/OR REPLACEMENT OF 6CC PISTON AUXILIARY PUMP (IF EQUIPPED) 4. Inspect running face on portblock (40). Grooving in the portblock, made evident when the surface is checked by dragging a fingernail across the surface, would be cause for replacement. Refer to Figure 11. 5. Inspect gerotor (41), O-ring (39) and end cap(25). Disassembly Assembly 1.
NOTE: Grooving in the valve plate and/or end cap, made evident when the surface is checked by dragging a fingernail across the surface, would be cause for replacement of the valve plate and/or end cap. REMOVAL, INSPECTION AND ASSEMBLY OF THE END CAP AND VALVE PLATE Refer to Figure 12. 2. Inspect and replace alignment pins (26) if bent or distorted. Disassembly 1. Using any combination of two, 9/16” wrenches or 9/16” socket and ratchet drive, loosen the end cap bolts (58) evenly. 2.
REMOVAL, INSPECTION AND ASSEMBLY OF THE CYLINDER BLOCK Assembly Refer to Figure 13. 3. Install one at a time, pistons, springs and seats as one assembly into the cylinder block. Disassembly 1. Tilt the pump on its side, drain remaining oil. Lift out the cylinder block assembly (38). 2. Remove the pistons, springs and piston seats. Inspection 1. Inspect the running surface of the cylinder block and piston ends for damage, nicks or unusual wear patterns.
REMOVAL, INSPECTION AND ASSEMBLY OF THRUST BEARING Refer to Figure 14. REMOVAL, INSPECTION AND ASSEMBLY OF SWASHPLATE AND CRADLE BEARINGS Disassembly Refer to Figure 15. 1. Remove the thrust bearing and race (17). Disassembly Inspection 1. Remove the swashplate (31). 1. Inspect the running surface of the bearing race for damage (17), nicks or unusual wear patterns. The running surface may show evidence of minor abrasion. This will be normal wear. Inspect the bearings for free movement.
REMOVAL, INSPECTION AND ASSEMBLY OF INPUT SHAFT Refer to Figure 16. NOTE: If trunnion arm is to be removed, delay reassembly of input shaft assembly. 5. Inspect and replace the thrust spring (20) and thrust washer (19) if they are distorted or broken. Assembly Disassembly 1. Remove the retaining ring (3). 2. Remove the lip seal (6). 3. Remove the spacer (4). 4. Remove the shaft assembly (1). Inspection 1. Inspect the input shaft (1) for worn splines, damage, or keyway damage.
REMOVAL AND INSPECTION OF TRUNNION ARM Refer to Figure 17. 15 Disassembly 12 1. Remove trunnion seal retainer and seal (12). 2. Remove the slot guide (14). 3. Remove the trunnion arm (13). Inspection 1. Inspect the trunnion arm (13) for wear or damage. Replace the trunnion arm if necessary. Assembly 1. Install the trunnion arm (13) into the housing (15) bore. Rotate the trunnion arm to verify free movement. 14 13 Figure 17.
Figure 17. PW / PY Pump 124 PW / PY Series BOXES INDICATE ITEMS INCLUDED IN KITS.
ITEM LIST - PW / PY SERIES Part numbers are not provided in this manual. No.
126 PW / PY Series
GLOSSARY OF TERMS Axial Piston: Type of design for hydraulic motors and pumps in which the pistons are arranged parallel with the spindle (input or output shaft). Bypass Valve: A valve whose primary function is to open a path for the fluid to bypass the motor or pump. Also referred to occasionally as the freewheel valve or dump valve. Case Drain Line (Return Line): A line returning fluid from the component housing to the reservoir.
Hydrostatic Transmission: The combination of a hydraulic pump and motor in one housing to form a device for the control and transfer of power. Inlet Line: A supply line to the pump. Integrated Hydrostatic Transaxle (IHT): The combination of a hydrostatic transmission and gear case in one housing to form a complete transaxle. Manifold: A conductor which provides multiple connection ports.
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