English 
Parts list
|
№ |
Number |
Name |
Qty |
|
1 |
395005017 |
BOOM SWING CYLINDER ASSY,R. H. |
1 |
|
2 |
395005018 |
BOOM SWING CYLINDER ASSY,L. H. |
1 |
|
3 |
395187012 |
ROD |
1 |
|
4 |
390601058 |
BUSHING |
1 |
|
5 |
395330011 |
RING NUT |
1 |
|
6 |
395273018 |
PISTON |
1 |
|
7 |
500468851 |
RING |
1 |
|
8 |
500252046 |
RING |
1 |
|
9 |
802250530 |
RING |
1 |
|
10 |
500213004 |
BUSHING |
2 |
|
11 |
395090011 |
CYLINDER, RIGHT |
1 |
|
12 |
395091011 |
CYLINDER , LEFT |
1 |
|
13 |
312705602 |
CYLINDER |
1 |
|
|
878000542 |
GASKET KIT |
1 |
|
14 |
|
GASKET |
1 |
|
15 |
|
O-RING |
1 |
|
16 |
|
O-RING |
1 |
|
17 |
|
RING |
1 |
|
18 |
|
O-RING |
1 |
|
19 |
|
GASKET |
1 |
|
20 |
|
RING WEAR |
1 |
|
21 |
|
SCRAPER RING |
1 |
|
22 |
|
GASKET |
1 |
|
23 |
|
O-RING |
1 |
|
24 |
801456086 |
SCREW |
1 |
Our advantage: original system data to ensure accurate size
Product Description
Heavy-Duty 878000542 Boom Swing Hydraulic Cylinder Seal Kit for Komatsu WB140-2 Backhoe Loaders
Eliminate dangerous boom swing drift and restore tight, zero-play lateral maneuverability in your digging operations with Toparts' premium 878000542 hydraulic cylinder service repair kit. Precision-engineered for the high-torque boom swing (slewing) cylinders fitted on Komatsu WB140-2 backhoe loaders, this overhaul kit is built to survive sudden directional shifts, heavy side-load forces, and severe vibration shockwaves.
The Toparts Engineering Difference: Built for Brutal Side-Load Stress
Backhoe loader boom swing cylinders operate under severe torsional and lateral loads. When digging against hard trench walls or dumping materials on uneven slopes, the swing cylinder experiences extreme side-load bending and sudden pressure spikes. Standard aftermarket seals quickly suffer from lip twist, flattening, or extrusion under these conditions, causing hydraulic fluid bypass and sloppy boom swing response. At Toparts, we manufacture our Komatsu-compatible kits with explicit material upgrades:
Mining-Grade P6000 Polyurethane Matrix: Our primary dynamic rod and piston seals are molded from advanced P6000 PU, offering 40% higher tensile strength and superior extrusion resistance under intense hydraulic shock loads compared to standard TPU.
Aggressive Environmental Mud Scraper: Features a rugged double-lip dust wiper system that actively shears off dry mud, silica sand, and moisture films from the extending rod, protecting internal sealing lips and cylinder walls from scoring.
Zero-Drift Heavy Pressure Containment: Precision-machined PTFE step seals backed by premium NBR energizers absorb continuous pressure spikes during sudden swing deceleration, maintaining tight holding force and eliminating swing drift.
High Elastic Memory Static Seals: All static O-rings and backup rings are formulated to resist compression set under continuous high oil temperatures up to 120°C, ensuring leak-free performance across the cylinder head interface.
Technical Specifications:
Brand Compatibility: Komatsu
Equipment Application: Backhoe Loaders (WB Series Utility)
Target Machine Match: Komatsu WB140-2 / WB140-2N
Seal Kit Part Number (P/N): 878000542
Application Component: Boom Swing / Slewing Hydraulic Cylinder
Material Matrix: High-Performance P6000 PU, Reinforced PTFE + Bronze, Premium NBR
Condition: 100% Brand New Industrial-Grade Aftermarket
Tag:Komatsu WB140-2 Boom Lift Cylinder Seal Kits,Komatsu WB140-2 Stabilizer Cylinder Seal Kits,Komatsu WB150-2 Arm Cylinder Seal Kits
