What are the reasons for oil leakage after installing the skeleton oil seal?

Common causes of oil leakage after installation of skeleton oil seal

1、 Installation issues (common)

Oil encapsulation reverse

The spring side and sealing lip are not facing the oil chamber, which directly leads to seal failure and oil leakage.

Installation skewed or tilted

When the oil seal is pressed in, it is not perpendicular, the lip is subjected to uneven force, and the local sealing is not tight.

Excessive impact and deformation

Directly hitting with a hammer can cause deformation of the outer ring of the oil seal, lip flanging, and spring detachment.

Not lubricated or improperly lubricated

Lip dryness caused by pulling during startup; The use of lubricating grease other than engine oil caused swelling.

Installation scale is incorrect

The sealing position deviates from the working surface due to insufficient or excessive pressure.

2、 Axis issue

Scratches, grooves, and wear on the shaft neck

The lip of the oil seal cannot fit tightly, resulting in a gap and oil leakage.

The surface roughness of the shaft is too large

Pulling the lip of the oil seal and damaging the seal.

The shaft has burrs and sharp corners

Cut open the lip of the oil seal directly.

Excessive shaft runout and eccentricity

During rotation, the lips cannot continuously adhere, resulting in periodic leakage.

3、 Problems with cavities/holes

The installation hole is deformed, out of roundness, and has burrs

The outer ring of the oil seal is not tightly sealed, causing oil leakage from the back.

The hole size exceeds the tolerance and is too large

The outer ring of the oil seal is too loose, causing creeping and rotation, resulting in oil leakage.

4、 The problem with the oil seal itself

Model and size do not match

The inner diameter, outer diameter, and height are incorrect, and the sealing surface does not fit properly.

Wrong material selection

The mismatch between temperature resistance and oil resistance leads to swelling, shrinkage, hardening, and cracking of the oil seal.

Poor quality of oil seal

Uneven lips, insufficient spring elasticity, and rubber defects.

5、 Working conditions and usage issues

Oil temperature is too high

Rubber aging, loss of elasticity, and sealing failure.

excessive stress

Exceeding the bearing range of the oil seal, the lip is blown open.

Impurities and dust entering

Wear the lip and form a leakage channel.

Poor exhaust and abnormal negative pressure

Causing the oil seal to be sucked open or oil to be thrown.