The crankshaft oil seal is probably one of the most important things under your hood. Its main purpose is to seal the openings on either end of the crankshaft—the front and the rear. It also helps maintain the crankcase seal, and while it is made from durable material able to withstand pressure, heat, and oil, this seal will wear out over time.
Depending on which type you're dealing with, a replacement can be easy. The front crankshaft oil seal can be repaired by any DIYer with the right directions, but unless you have all the right equipment, it is advisable to have the rear crankshaft oil seal replaced by an auto mechanic.
Step 1 - Lift the Car
Before you begin you'll need to jack up the car. Use a lug nut wrench to remove the front wheel and place the jack stand under to support it.
Step 2 - Remove the Belt
Next, you need to remove the serpentine belt from the engine. Place a medium length breaker bar on the tensioner and lift. Pull the belt out from the alternator and pull it off the crankshaft to completely remove it.
Step 3 - Take Out the Splash Shield
The splash shield that houses the front crankshaft oil seal will have to come off as well. This is located inside the wheel well next to the engine. To remove it, start by pulling out the push pins on top. Then, use a panel remover to take out the center of the pin before you remove the rest. Once all the push pins are out, you can get remove the shield as well.
Step 4 - Take Out the Crankshaft Oil Seal
Remove the bolt holding the crank pulley; then, take out the bolts and the pulley itself. You should now be able to see the crankshaft.
Pry out the shield, which is the round ring-like metal situated on the center, using a screwdriver to get to the oil seal.
Step 5 - Insert New Seal
Before you make the replacement, check out how deep it goes to make sure that you are able to properly fit it with a new one. If it goes too deep for you to pull out, then you will want to take the vehicle to professional instead of continuing.
Once the old seal is out, slide the new one into place. Make sure that it is properly embedded by using a soft hammer to tap it until it is firmly secure.
Step 6 - Replace Everything
After you have placed the new crankshaft oil seal, you can put the shield back on and tighten it with the all the bolts you took out. Put back the splash shield and replace the push pins as well before you fit the serpentine belt where it belongs. Make sure that the bolts and the belt are properly placed before putting the wheel back in.