YN15V00037R450 Seal Kit for Kobelco SK200-8: Prevent Leaks and Protect Your Final Drive

The YN15V00037R450 Seal Kit is designed for the hydraulic travel motor used on the Kobelco SK200-8 excavator.

The travel motor is one of the most heavily loaded hydraulic components on a Kobelco SK200-8 excavator. Every time the machine moves forward, reverses, turns, or climbs uneven ground, the travel motor must convert hydraulic pressure into the torque needed to drive the tracks.

Because the travel motor operates under high hydraulic pressure and repeated load changes, its sealing components are critical. Once the seals begin to wear, harden, crack, or lose elasticity, hydraulic oil leakage can occur and travel performance may gradually deteriorate.

What components are included in the YN15V00037R450 seal kit?

Seal Component	Typical Material / Type	Application	Main Function
O-Rings	High-pressure resistant elastomers in various diameters and cross-sections	Used at motor housing joints, valve block interfaces, and other static sealing surfaces	Provide static sealing and prevent hydraulic oil leakage between mating components
Oil Seal	Reinforced rotary oil seal	Installed at the main output shaft of the travel motor	Prevents hydraulic oil from leaking outward and helps keep external contaminants from entering
PTFE Seals / Glide Rings	PTFE-based low-friction sealing rings, often used with elastomer energizers	Used in high-frequency reciprocating or rotating sealing areas, including piston and cylinder block related positions	Provide wear-resistant, low-friction sealing under dynamic operating conditions
Back-up Rings	Nylon or PTFE	Installed together with O-rings in high-pressure areas	Support O-rings and help prevent extrusion, deformation, and damage under high pressure
Dust Seals / Wiper Seals	Wear-resistant elastomer or polymer sealing material	Installed at exposed sealing positions	Help prevent dust, mud, water, and other external contaminants from entering the motor

Common Signs of a Travel Motor Seal Failure

Travel motor sealing problems may develop gradually. A small leak can eventually lead to reduced hydraulic efficiency or contamination if it is ignored.

Common symptoms include:

Hydraulic Oil Leakage Around the Travel Motor

Visible hydraulic oil around the motor housing, valve block, flange, or sealing surfaces is one of the most obvious warning signs.

Before disassembling the motor, clean the area thoroughly and confirm the actual source of the leak. Oil can travel along hoses and housings, making the leak appear to originate from a different location.

Weak Travel Performance

If one side of the excavator travels more slowly than the other, the cause may include excessive internal hydraulic leakage.

A worn seal does not automatically mean the entire motor is damaged, but poor sealing can contribute to pressure loss and reduced efficiency.

Excavator Pulls to One Side

When one travel motor produces less torque or speed than the other, the machine may drift or pull toward one side.

However, this symptom can also be caused by the main pump, control valve, swivel joint, brake system, or track condition, so the complete hydraulic system should be checked.

Increased Case Drain Flow

An abnormal increase in motor case drain flow can indicate excessive internal leakage.

This may result from seal deterioration, but it can also indicate wear of the cylinder block, pistons, valve plate, or other internal hydraulic components.

Hydraulic Oil Temperature Increases

Excessive internal leakage converts hydraulic power into heat.

If a travel motor becomes unusually hot, check:

• Hydraulic oil condition
• System pressure
• Case drain flow
• Internal leakage
• Travel motor bearings
• Brake release operation

Travel Motor Seal Kit vs. Final Drive Floating Seal

One point that is often confusing is the difference between a travel motor seal kit and a final drive floating seal.

The YN15V00037R450 is primarily a hydraulic travel motor sealing kit containing internal hydraulic seals and O-rings.

The YN15V00037 final drive assembly also uses a separate floating seal within the reduction gearbox section; parts breakdowns list YN15V00037S029 as a seal in the final-drive assembly.

If the leak is from the hydraulic motor section, YN15V00037R450 may be the required kit.

If gear oil is leaking from the final drive gearbox / hub area, the floating seal or other gearbox seals may need attention instead.

This distinction can prevent unnecessary parts replacement.

What Should Be Inspected When Replacing YN15V00037R450?

Replacing a seal kit without inspecting the rest of the travel motor can lead to repeat leakage.

During disassembly, technicians should inspect the following components.

Shaft and Oil Seal Surface

Check the shaft contact area for:

• Grooves
• Scoring
• Corrosion
• Uneven wear

Installing a new oil seal onto a badly worn sealing surface may cause the new seal to leak again.

O-Ring Grooves

Inspect all O-ring grooves for:

• Scratches
• Burrs
• Corrosion
• Dirt
• Old seal residue

The groove must be clean and undamaged before the new O-ring is installed.

Cylinder Block and Pistons

Check for abnormal scoring, wear, heat discoloration, or damage.

Excessive wear between the pistons and cylinder block can increase internal leakage even when all seals are new.

Valve Plate

Inspect the contact surface for:

• Scoring
• Grooves
• Cavitation
• Heat damage
• Uneven wear

A damaged valve plate can result in pressure loss and excessive leakage.

Bearings

Check bearings for abnormal clearance, rough rotation, pitting, or damage.

Bearing problems can cause shaft movement and may shorten the life of newly installed seals.

Travel Motor Seal Kit vs. Final Drive Floating Seal

One point that is often confusing is the difference between a travel motor seal kit and a final drive floating seal.

The YN15V00037R450 is primarily a hydraulic travel motor sealing kit containing internal hydraulic seals and O-rings.

The YN15V00037 final drive assembly also uses a separate floating seal within the reduction gearbox section; parts breakdowns list YN15V00037S029 as a seal in the final-drive assembly.

Installation Tips for YN15V00037R450

Good installation practice is essential to getting full service life from the new seal kit.

Before installing the seals:

1. Thoroughly clean the travel motor exterior before disassembly.
2. Prevent dirt from entering open hydraulic passages.
3. Remove old seals carefully without scratching sealing surfaces.
4. Clean O-ring grooves and mating surfaces.
5. Compare each new seal with the removed seal before installation.
6. Lubricate compatible seals with clean hydraulic oil before assembly.
7. Do not twist or stretch O-rings excessively.
8. Protect seals when passing them over splines, threads, or sharp edges.
9. Tighten bolts evenly to the specified torque.
10. Fill and bleed the hydraulic system correctly before full-load operation.

After the repair, initially operate the travel motor at low load and inspect the motor carefully for leaks.

Do Not Diagnose a Travel Motor by Leakage Alone

A leaking travel motor does not necessarily mean the hydraulic motor itself must be replaced.

Likewise, installing a new seal kit will not solve every travel problem.

Before rebuilding the motor, check:

Hydraulic pressure → travel flow → case drain → brake release pressure → swivel joint → control valve → track condition → internal motor condition.

If pressure and flow are normal but case drain is excessive, internal motor wear becomes more likely.

If case drain is normal but external oil leakage is visible, replacing damaged seals may be sufficient.

A systematic diagnosis can reduce unnecessary repair costs.

How to Prevent Leaks in Your Kobelco SK200-8 Travel Motor？

The YN15V00037R450 Travel Motor Seal Kit for Kobelco SK200-8 provides the internal sealing components required during travel motor repair.

Replacing deteriorated oil seals, O-rings, and sealing rings can help control hydraulic leakage and maintain reliable travel performance. However, the condition of the shaft, bearings, cylinder block, valve plate, and other internal components should always be checked during disassembly.

If these components are badly worn, replacing seals alone may provide only a temporary solution.

For the best repair result, identify the leak source first, confirm the exact travel motor number, inspect the internal components, and install the correct seal kit using clean hydraulic-repair procedures.

Send Faseals your Kobelco model, travel motor part number, and clear photos of the motor.

We can help you confirm whether YN15V00037R450 is the correct travel motor seal kit before ordering.