How To Replace A Front Crankshaft Oil Seal

 If you notice oil leaks under your vehicle engine the front crankshaft seal could be the culprit. The crankshaft seal, located in front of the engine, circulates oil back into the oil pan to keep it form leaking as the crankshaft rotates. You should be able to replace the crankshaft seal yourself by following these steps.

Prepare to Replace the Crankshaft Seal

To replace the crankshaft seal, gather:

  • work gloves
  • jack stands
  • wheel chocks
  • rags
  • assorted screwdrivers
  • assorted wrenches 
  • breaker bar (optional)
  • socket set
  • torque wrench
  • strap wrench
  • socket set
  • soft hammer
  • gear puller
  • seal puller (optional) 
  • panel remover 
  • motor oil
  • new crankshaft seal

Turn off the engine, and park the vehicle on a flat area that has plenty of light. Raise it enough on jack stands to easily access the harmonic balancer, an accessory on the crankshaft on the front of the engine, and secure the back wheels with wheel chocks. Refer to your manual for suggested jacking points and location of parts.

Remove the Serpentine Belt and Harmonic Balancer

Prop the hood, and disconnect the negative battery cable, which usually has a negative sign. Locate the serpentine belt and the spring-loaded tensioner, and snap a picture to help you recall how it connects. Use the correct tool to remove the belt by loosening the tensioner, which is commonly a ratchet, open-end wrench, or breaker bar, then set the parts aside..

Secure the harmonic balancer bolt with a strap wrench, and use the breaker bar or the correct socket to disconnect it, pulling the bolt as hard as you can while you turn it left. 

Remove the harmonic balancer with the gear puller, inserting the hook in a place that won't break. Some models may feature a threaded bolt for attaching the gear puller, a device with three slots. Attach a ratchet or breaker bar, and tighten the center bolt until the balancer comes loose.

Detach the center pin on the shield housing the crankshaft on the inside of the wheel well. Remove the rest of the pins, and use the panel remover to remove the shield.

Replace the Seal

Remove the crank pulley bolt, and use the screwdriver or seal puller to break the seal from the timing chain. It may take several tries to break the seal.

Apply a fresh coat of motor oil to the new soil to prevent tearing. Clean the seal area, and install the new seal in place of the old one.

Press it down with the lip aiming at the engine block, and gently tap it with the hammer to secure it. Reinstall other parts, referring to pictures, tightening bolts to the suggested torque with the torque wrench. Reconnect the battery cable, and lower the vehicle.

You can also take your car to an auto repair professional.