Which way do I install the oil seal?
We receive this question quite regularly: Which way do I install this oil seal?
The above picture shows the cross section of a single lipped oil seal. The side with the spring and recess always faces the oil you are trying to contain.
Crank seals on the drive side or primary side are meant to retain the oil level in the chain case. The seal is installed with the spring facing out toward the primary case.
Seals in the timing cover on the opposite end of the crankshaft are retaining oil pressure in the cover. An example of this is the timing side crank oil feed seal.
Gearbox seals retain gear oil so to spring goes towards the inside of the gearbox.