If the wheel seal lip is installed facing away from the fluid, the seal is

• A. Sealing properly
• B. Likely to leak
• C. Will not seal
• D. Will seal only under pressure

Answer: (B)

The sealing edge must face the fluid to form a tight barrier. The lip is shaped to ride against the rotating surface and, with the preload from the spring, press into the bore to keep lubricant in and contaminants out. When the lip is installed facing away from the fluid, that sealing edge doesn’t contact the fluid correctly, so the lip cannot block the path the lubricant would take to escape. Fluid can seep past the lip, making leakage likely. The idea that it would seal only under pressure or that it would seal perfectly if oriented differently isn’t supported here—the backward orientation undermines the seal’s ability to do its job, so leakage is the expected result.