2005 Mazda MPV - Crankshaft Seal

Crankshaft Seal Replacement

The crankshaft seal is designed to prevent oil from leaking around the end of the crankshaft and out of the crankcase. Crankshaft seals are located at the front of the engine's crankshaft behind the main crankshaft pulley or harmonic balancer, and are installed in a housing or timing cover that surrounds the crankshaft. The two main components of the seal include a sealing ring and spring. The ring is made of rubber or synthetic material to resist heat, pressure, and wear, and the spring helps to maintain pressure on the sealing ring to ensure a reliable seal. Over time, the crankshaft seal can dry out, tear, break, or wear a groove in the balancer shaft, allowing excessive clearance and causing oil to leak. If the balancer or crankshaft pulley shaft has worn due to a brittle or hard seal, it may also be necessary to install a sleeve to restore the appropriate clearance and eliminate the groove when you replace the crankshaft seal. A failed or damaged crankshaft seal can allow oil to seep or leak around the crankshaft, and you may notice oil puddles under your vehicle after it is parked overnight or oil sprayed around the front of the engine from the crankshaft's rotation. If left unrepaired, the loss of oil can cause serious damage to your engine, and you also see significant grease buildup due to oil loss near the seal. Replacing a crankshaft seal typically involves removing the engine belt and the harmonic balancer or crankshaft pulley, and the crankshaft seal is usually press-fit and must be driven into the cover until flush. For your next crankshaft seal repair, shop O'Reilly Auto Parts for the replacement crankshaft seal you need to complete your repair.