31Y1-18061 Boom Cylinder Seal Kit 85mm Rod 120mm Bore for Hyundai Excavator R200W-7 R210NLC-7

31Y1-18061 Boom Cylinder Seal Kit

31Y1-18061 is a boom hydraulic cylinder seal kit used on selected Hyundai R200W-7 and R210NLC-7 excavators. The applicable boom cylinder uses an 85 mm rod and 120 mm bore, with the same seal kit serving the left-hand and right-hand boom cylinders.

Fitment should not be confirmed by excavator model alone. Hyundai used different boom cylinder seal kits across production ranges, so the machine serial number and cylinder assembly number should be checked before ordering.

R200W-7 and R210NLC-7 Serial Number Fitment

For the Hyundai R200W-7, 31Y1-18061 is listed for boom cylinder assemblies 31N6-53120 (LH) and 31N6-53110 (RH) through machine serial number #0614. Machines from #0615 use a different boom cylinder seal kit configuration.

For the Hyundai R210NLC-7, 31Y1-18061 is used with the same LH and RH boom cylinder assembly numbers through serial number #0268. From #0269 onward, the catalog specifies a different seal kit. Always confirm the serial number when replacing seals on these machines.

Cylinder Inspection Before Seal Replacement

Before rebuilding the boom cylinder, inspect the 85 mm piston rod for scoring, corrosion and chrome damage. Check the 120 mm cylinder bore, piston, gland and seal grooves for wear that could cause a new seal kit to leak prematurely.

Clean all cylinder components before assembly and verify the installation direction of the rod seals, piston seals, backup rings and wipers. If the rod or bore surface is damaged, replacing the seal kit alone may not correct the hydraulic leakage.

Topvelsun Seal Kit Supply

Topvelsun supplies excavator hydraulic cylinder seal kits with 1-piece MOQ and a 6-month warranty. For accurate confirmation, provide the part number, machine model, serial number or boom cylinder assembly number before ordering.

Product photos may show different packaging or seal brands used for the same 31Y1-18061 application. Brand and packaging can vary by supply batch; confirm any specific brand requirement before ordering.