123-2233 Hydraulic Pump | AP12 Main Hydraulic Pump Assembly Product Identification Core Part Details Primary Part Number: 123-2233 Standard Numeric Format: 1232233 Part Name: AP12 Main Hydraulic Pump Assembly (Double Piston Hydraulic Main Pump for Excavator) Equipment Applications Compatible Caterpillar Models Primary Models: Caterpillar E320B (including E320B L Long Undercarriage version) Equipment Type: Medium Hydraulic Excavator (Construction & Earthmoving) Application System: Main Hydraulic Power System Serial Number Fitment: Varies by prefix (1XS, 4XN, 9JS, 5BR), verify before purchase Manufacturer Note: Often produced by Mitsubishi or Uchida-Rexroth for Caterpillar Related Part Numbers Associated E320B Hydraulic Pump Series Related Part Numbers for E320B: 114-0602 (early/regional versions), 0R-7313 (Remanufactured assembly), 126-2016 (E320B L/specialized versions) Core Repair Components AP12 Series Replacement Parts Cylinder Block (Pump Barrel): Holds 9 pistons (core pressure-generating component) Piston Shoe: Sold in sets of 9 pieces per pump side Valve Plate: Critical for timing, left and right versions must be distinguished Set Plate (Retainer Plate): Secures piston shoes to swash plate Swash Plate (Cradle): Core component for pump displacement control Pilot Pump (Gear Pump): Mounted at rear, part number 117-6663 Seal & Control Parts Main Pump Seal Kit: Part number 123-2233SK (varies by pump assembly) NFC (Negative Flow Control) Valve: Prevents engine bogging down when functioning properly Product Function & Features Component Category: Hydraulic System Core Parts Function: Supplies high-pressure hydraulic fluid for excavator boom, arm, bucket, swing and travel operations Design: Double piston pump optimized for Caterpillar E320B medium excavator hydraulic systems Related Part Numbers NO P.N. NAME 1 369-9676 369-9676 247-8968 Main Hydraulic Pump for CAT 374D 365C 2 569-40-42502 569-40-42502 569-40-63302 Steering Valve Assembly fits Komatsu HD465 a... 3 448-9705 448-9705 Hydraulic Pump GP-PS-B for CAT C4.4 C7.1 320GC 930M 4 600-463-6201 Komatsu Electronic Control Unit 600-463-6201 ECU 5 4439384 Hitachi EX1900/2500/2600/3600/5500 Swing Motor 4439384 4439491 6 4436203 Hitachi EX2500/3600/8000 Hydraulic Pump 4436203 7 9285566 9285566 YB60000770 Main Hydraulic Pump Assembly for Hitachi ZAX130 8 6261-41-9500 Komatsu Valve Assembly 6261-41-9500 for PC200-7 PC220-7 PC300-7 9 561-30-81101 Wheel Rim Assembly 561-30-81101 for Komatsu Heavy-Duty Machinery 10 723-66-21400 Komatsu 723-66-21400 Main Control Valve Assembly for D375-6 Crawler Do... 11 3417674 Cummins 3417674 Fuel Injection Pump for N14 / M11 / ISM11 Engine Serie... 12 102-0783 102-0783 Hydraulic Main Pump for Caterpillar E307 307.5 13 377-4959 377-4959 Hydraulic Main Pump for CAT 390GC 390FL C18 C27 Excavator 14 14723835 14723835 Main Hydraulic Pump for Volvo ECR88 ECR88 AP2D36 15 6261-41-4900 EGR Valve Assembly 6261-41-4900 for Komatsu PC450-8 16 393-3606 Seal Kit 393-3606 for Caterpillar (CAT) Hydraulic Cylinder Systems 17 4689079 Hitachi EX1900-5 EX1900-6 Hydraulic Pump 4689079 18 723-43-13400 723-43-13400 Main Control Valve Assembly for Komatsu WA470-6 Wheel Loa... 19 600-815-9650 Komatsu Heater 600-815-9650 for HD785-7 rigid dump truck 20 723-65-21700 723-65-21700 Main Control Valve for Komatsu D155AX-6 21 705-95-05140 Komatsu Hydraulic Pump 705-95-05140 for HD605 22 216-0038 216-0038 Hydraulic Main Pump for CAT 330C C9 Excavator Parts 23 6218-81-4111 Komatsu Sensor Assembly 6218-81-4111 Blowby - HD785-7 PC1250SP-8R SAA1... 24 708-1S-00240 708-1S-00240 Fan Pump Hydraulic Fan Pump for Komatsu D65-12 Crawler Do... 25 708-2H-00453 Main Hydraulic Pump 708-2H-00453 708-2H-00450 for Komatsu PC400-7/450-... 26 207-60-71182 207-60-71182 Filter Element for Komatsu PC600 WA470 27 702-16-01531 Komatsu Pilot Valve 702-16-01531 for D375A bulldozers 28 702-75-01900 Komatsu Valve Assembly 702-75-01900 for PC750SE-7 29 21N-68-32680 Komatsu PC1250-7 Solenoid Valve 21N-68-32680 30 600-051-2180 Komatsu Clip 600-051-2180 for D65 WA470-6 GD675
