Hyundai 110D-7E Operating Manual page 185

After the unit to be sealed is assembled, a post-assembly leakage test can be performed to
insure the seal is properly installed. A vacuum check is recommended rather than a pressure
check as vacuum checks are more sensitive. Many users find this an easy check to combine
with a vacuum fill technique for the lubricant. It is recommended the compartment be filled to the
correct level with lubricant and then rotated slowly several revolutions to seat the seals.
A vacuum test will catch big seal damage such as broken seal rings or cut torics that may be
caused in the last phases of assembly. The Duo-Cone seal is not designed to seal air, so some
leakage can be expect using such a procedure.
Following these guidelines and recommendations should insure optimum performance from the
Duo-Cone-Seals.
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