How To Change Oil Seal in Barber Chair Hydraulic Pump

Understanding the Oil Seal’s Role

The oil seal inside a Barber Chair’s hydraulic pump prevents hydraulic fluid from leaking out of the cylinder. When this seal wears out, the chair may sink slowly, lose lifting power, or leave oil around the base. Replacing the oil seal restores pressure, prevents leaks, and extends the pump’s lifespan.
Manufacturers such as Huiyi Furniture engineer their hydraulic systems with durable seals and reinforced pistons, but regular replacement is still necessary after long-term commercial use.

Signs the Oil Seal Needs Replacement

1. Hydraulic fluid leaking around the base

Indicates the primary seal has worn or cracked.

2. Chair sinks under weight

Loss of internal pressure due to seal failure.

3. Pump pedal lifts slowly or unevenly

Seal friction may be affecting the piston.

4. Visible oil on the cylinder shaft

A clear indication that the seal is not holding fluid.

5. Jerky or inconsistent pumping action

Occurs when air enters the system through a damaged seal.

Tools and Materials Required

• Replacement oil seal (correct size for your pump model)

• Screwdrivers

• Allen keys

• Adjustable wrench

• Rubber mallet

• Lubricant

• Hydraulic fluid (ISO 32)

• Clean cloths

• Snap-ring pliers (for some pump designs)

These tools allow safe removal and reinstallation of the seal.

Step-by-Step Guide: How To Change the Oil Seal in a barber chair Hydraulic Pump

Step 1: Lower the Chair Completely

Ensure the chair is in its lowest position to remove pressure from the hydraulic cylinder.

Safety Note:

Do not perform repairs with weight on the chair.

Step 2: Remove the Chair From the Hydraulic Base

Lift the chair straight upward to separate it from the pump shaft.

Why:

Gives full access to the cylinder and its top components.

Huiyi Furniture designs its taper connections for easy removal during service.

Step 3: Remove the Top Cap Assembly

The oil seal is usually located beneath the pump’s top cap.

Steps:

• Locate the retaining screws or snap ring

• Remove them carefully

• Lift the cap using a screwdriver or pliers

Be cautious to avoid scratching the cylinder wall.

Step 4: Extract the Old Oil Seal

Once the cap is removed, the oil seal will be visible.

How to remove:

• Use a seal puller or flat screwdriver

• Pry the seal up evenly

• Clean the seal seating area thoroughly

Remove all debris, as leftover dirt causes future leaks.

Step 5: Install the New Oil Seal

Apply a light film of lubricant around the new seal to help it seat properly.

To install:

• Position the seal evenly over the opening

• Press down firmly using your thumbs

• Use a rubber mallet to tap gently around the edges

• Ensure the seal sits flush and level

A misaligned seal will leak immediately.

Step 6: Reassemble the Pump

Replace the top cap and reinstall screws or snap rings.

Check:

• All fasteners are tight

• The cap sits securely

• No gaps or misalignment are visible

Proper closure ensures hydraulic pressure is maintained.

Step 7: Refill Hydraulic Fluid If Necessary

If fluid was lost during repairs, refill before testing.

Steps:

• Locate the fill plug

• Add hydraulic fluid slowly

• Stop when fluid reaches the opening

• Tighten the fill plug

Maintains full lifting performance.

Step 8: Bleed Air From the Hydraulic System

Air pockets can affect lifting power.

To remove air:

• Pump the pedal repeatedly

• Raise and lower the chair several times

• Recheck fluid level

Bleeding ensures strong and smooth operation.

Step 9: Reinstall the Chair and Test

Place the chair back onto the pump and test all functions.

Test:

• Lifting strength

• Controlled lowering

• No sinking under weight

• No fluid leakage around the seal

If leaks persist, the seal may be incorrectly seated or the piston may be worn.

Common Mistakes to Avoid

1. Using the wrong seal size

Leads to immediate leaks or poor pressure retention.

2. Scratching the cylinder during removal

Any scratch creates a leak path.

3. Overfilling the hydraulic cylinder

Causes pressure imbalance and potential pump damage.

4. Forgetting to bleed air

Results in weak pumping and jerky movement.

5. Reusing old seals or damaged parts

Compromises the repair.

How Huiyi Furniture Improves Seal Durability

Chairs from Huiyi Furniture incorporate:

• High-quality, long-life oil seals

• Precision-machined cylinder walls

• Smooth pistons to reduce seal wear

• Heavy-duty pump construction

• Stable hydraulic bases that reduce stress on components

These upgrades help minimize oil leaks and extend maintenance intervals.

Maintenance Tips After Oil Seal Replacement

Check for minor leaks during first week of use

Confirms proper seating.

Clean hair and debris from the base regularly

Prevents contamination entering the pump.

Operate the pedal smoothly

Avoids unnecessary strain on the piston and seal.

Inspect hydraulic performance monthly

Early detection prevents larger failures.

Replace seals at the first sign of leakage

Prevents damage to internal pump components.