There are six failure modes that will account for virtually all of the premature failures of a Scotseal:
- Improper installation (wrong tool, or no tool used)
- Cocked installation
- Improper bearing adjustment
- Seal spinning on the spindle (hit spindle, or imperfections in spindle)
- Hub imperfections
- Installed over a wear ring
| Cutaway | ||
| Seal designs are most often represented by a flat view of the seal cut crosswise, like the one shown below. Only the top cross section is used. The shaft, or in this case axle spindle, is represented by the base line. The wheel hub is indicated at the top. A Scotseal is installed first into the hub and then mounted on the spindle. In this illustration, the bearing side (or oil side) is to the left and the outside (or air side) is to the right. |  |
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| The three-quarter view to the right shows how the flat drawing is derived from the three-dimensional seal. Some common terms used throughout this guide follow. |  |
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| Main components | ||
The main components of the seal are: (A.) the inner cup, |
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| Sealing elements | ||
The Scotseal is a unitized seal, which means all of the sealing surfaces are protected inside the seal. The sealing lips remain stationary on the shaft, while the outer cup rotates with the hub and wheel. The last item, Bore-Tite, is unique to seals from SKF. This distinctive green material is a non-hardening sealant that helps fill small imperfections in the bore without reducing the heat dissipating ability of the seal. The sealing elements are: (A.) the primary sealing lip, |
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