YN32W01006P1 Swing 2nd Sun Gear 23T for Excavator Kobelco SK200-5 SK200-6 SK200LC-6 SK210LC

YN32W01006P1 Swing 2nd Sun Gear

The YN32W01006P1 sun gear is used in the second planetary reduction stage of selected Kobelco excavator swing gearboxes. Its cylindrical gear body transfers torque through the planetary gear set as swing motor speed is reduced before driving the excavator upper structure.

This 23-tooth design has a relatively long working gear surface compared with shorter sun gears used elsewhere in a swing reduction system. Correct tooth geometry, bore fit and axial position are important for maintaining stable engagement across the full gear width.

Because the component works under repeated acceleration, braking and reverse swing loads, both tooth condition and gearbox alignment should be checked when the original gear shows abnormal wear.

Why Full-Width Tooth Contact Matters

A long sun gear should show a reasonably even contact pattern across its working tooth surface. When load becomes concentrated near only one end of the teeth, the problem may not be limited to the gear itself.

Bearing wear, carrier movement or incorrect axial positioning can change the way the planetary gears contact the sun gear. Continued operation under this condition can accelerate pitting and edge wear.

Inspecting the complete reduction stage before reassembly can help prevent a new gear from developing the same wear pattern.

Typical Wear on a Swing Sun Gear

• Pitting or surface fatigue along the working tooth faces

• Chipped or cracked tooth edges

• Uneven wear concentrated at one end of the gear teeth

• Scoring or excessive clearance around the center bore

• Heat discoloration caused by lubrication or friction problems

• Metal particles found in the swing gearbox oil

If the wear pattern is uneven around the circumference, inspect the planetary carrier, mating gears and bearings before rebuilding the swing reducer.

Second-Stage Position Is Part of the Identification

A swing gearbox can contain more than one sun gear. Similar-looking gears from different reduction stages should not be assumed interchangeable simply because they are used in the same excavator model.

Tooth count, overall height, outside diameter, center bore and reduction-stage position should all match the original component.

This is particularly important on older excavators where the installed swing gearbox may have been replaced or rebuilt during previous service.

Information Needed for Fitment Verification

For a more reliable identification, send the following information with your inquiry:

• Excavator model and machine serial number

• Swing reduction gearbox information

• Clear photos of both sides of the original sun gear

• Confirmed tooth count

• Outside diameter and center bore diameter

• Overall gear height

These details help distinguish sun gears used at different reduction stages and reduce the risk of selecting a visually similar but incorrect part.

Kobelco Swing Gear Parts Support from Topvelsun

Topvelsun supplies replacement sun gears and other internal swing reduction components for excavator gearbox rebuilding, equipment repair and parts distribution.

Send us part number YN32W01006P1 or cross reference 72210018 together with your machine and original gear information, and we can help verify the application before quotation.