How to Replace a Rope Seal With Neoprene

Older vehicles use graphite rope seals as the rear main seal, while newer vehicles employ neoprene rubber. The rear main seals basic purpose is to prevent engine oil from escaping between the rear of the crankshaft and the block. Over time, these seals deteriorate and eventually fail, resulting in a very expensive engine repair bill or -- if you plan to do the task yourself --a very messy repair job. Swapping your vehicles old rope seal for a longer-lasting neoprene seal ensures you wont have to perform the same job again in the future.

Instructions

1

Grab the rope seal from the lower bearing cap with a pair of needle-nose pliers. Carefully pull the seal off the cap without scratching or damaging the cap itself. Clean the RTV silicone residue off of the cap before proceeding.

2

Lubricate one side of the neoprene seal and slide it onto the groove in the main cap. Make sure the split part of the lip is facing the front of the engine. When finished, set the cap aside and cover it, to prevent debris contamination.

3

Grab the upper rope seal with a pair of needle nose pliers and turn the crankshaft in the direction the crankshaft normally rotates, while pulling, to remove the rope seal. If the rope seal breaks mid-way, push the remnants of the seal out with a piece of stiff copper wire. Clean off the RTV silicone residue from the block before proceeding.

4

Lubricate one side of the neoprene seal and carefully slide the seal into the block. Make sure the lip on the seal is facing the front of the engine.

5

Add a thin coat of RTV silicone to the cap-to-block mating surface on the main cap and on the chamfered edge. Apply clean motor oil onto the main bearing for lubrication; making sure the bearing itself is seated within the cap.

6

Insert the side seals into the grooves on the side cavities of the main bearing cap. If your engine does not use side seals, fill the cavities with RTV silicone after reinstalling the cap.

7

Install the cap back into the block and torque the cap down with a torque wrench. Consult the automotive service guide for your vehicle for detailed information on torque specifications.