2478998 247-8998 2590635 259-0635 Boom Arm Bucket Hydraulic Cylinder Excavator Seal Kit

2478998 247-8998 2590635 259-0635 Boom Arm Bucket Hydraulic Cylinder Excavator Seal Kit

Version 1 (Boom & Arm Cylinder Rebuild Focus)

Excavator boom and arm hydraulic cylinder rebuilds require the seal kit containing 2478998 for primary boom lift circuits. The bucket cylinder sealing configuration uses 2590635 to maintain pressure during aggressive digging cycles. When servicing the arm crowd function, part number 247-8998 provides critical sealing for the piston rod dynamic zone. The boom holding circuit identified as 259-0635 complements the kit by sealing the counterbalance valve ports. Excavator operators notice improved arm curl force after installing 2478998 and 2590635 together. The bucket tilt system featuring 247-8998 and 259-0635 shows reduced leakage during full-load dumping operations. Every boom cylinder overhaul should verify that 2478998, 247-8998, 2590635, and 259-0635 are all present before reassembly to ensure complete sealing coverage.

Version 2 (Application & Bucket System Focus)

Heavy equipment workshops stock 2478998 as the primary seal for excavator boom and bucket hydraulic cylinders. The 2590635 seal kit pairs effectively with 247-8998 for arm cylinder gland retention. When rebuilding a bucket tilt cylinder, include 259-0635 to prevent internal cross-port leakage. Part number 2478998 (also referenced as 247-8998 in some catalogs) protects the boom piston from pressure spike damage. The arm cylinder using 2590635 and 259-0635 demonstrates consistent extension speeds under variable loads. Excavator bucket cylinders fitted with 2478998 and 247-8998 show zero weeping after 2000 operating hours. Field technicians prefer 2478998, 2590635, 247-8998, and 259-0635 for comprehensive boom-to-bucket sealing coverage across multiple excavator models.