Repair 7

How to Modify a Cub Crank Rear Seal Retainer

The rear seal for your cub crank is found right behind the main bearing journal on your vehicles crankshaft. This seal is used to keep the oil inside the crankshaft and the oil pan. If you have noticed oil leaking from the back of your vehicles crankshaft, you probably need to replace this seal. Having a mechanic replace this seal could easily cost $200 to $300. However, if you do it yourself, you can replace the seal for about $50.

Instructions

1

Remove the oil filter by unscrewing it. Remove the oil nut with a nut driver and allow the oil to drain into a drain pan. Use the nut driver to remove the radiator fluid nut from the engine. Allow the radiator fluid to drain into another drain pan.

2

Use a wrench to remove the motor mounts from your engine. Disconnect the radiator hoses, the fan and the fan shroud from your engine. Use a wrench to unbolt the engine from the vehicles transmission if needed.

3

Use a jack to raise the engine off of the engine mounts. Use a wrench to remove the oil pan from the engine. Pull the oil pan from the engine and use a nut driver to remove the bolts from the oil pan.

4

Pry the bearing cap off of the oil pan with a putty knife. Make sure that you do not scratch the crankshaft. Use a brass punch to remove the upper part of the seal. Tap the brass punch with a hammer until the seal comes off of the oil pan.

5

Install your new seal to the oil pan. Rotate the crankcase shaft while holding the seal on the oil pan. Use a sealer to make sure that your new seal will retain the oil. Reinstall the oil pan on the engine. Use your nut drivers to secure the oil pan bolts on the engine.

6

Lower the engine and remove the jack. Reinstall the transmission to the engine. Reinstall the fan shroud, the fan and the radiator hoses on your engine. Replace the motor mounts to secure the motor in place. Refill the engine oil and the radiator coolant.