Thread: Remind me--whats involved in 305 rear main seal replacement?

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Brian, I know you're no beginner, but will link the procedure with photos in the event someone else with less experience than you needs to do this also.
http://www.pavementsucks.com/tech/rearmain.php

1982-85 EXC. V6-173
These engines are equipped with two-piece, helix type rear seal. A seal starting tool, Fig. 23, must be used to prevent the upper seal half from coming into contact with the sharp edge of the block. When necessary to correct an oil leak due to a defective seal, always replace the upper and lower seal halves as a unit. When installing either half, lubricate the lip portion only with engine oil, keeping oil off the parting line surface as this is treated with glue. Always clean crankshaft surface before installing a new seal.


To replace the lower seal, remove seal from groove in bearing cap, using a small screwdriver to pry it out.
Insert new seal and roll it in place with finger and thumb.
To replace the upper seal (with engine in car) use a small hammer and tap a brass pin punch on one end of the seal until it protrudes far enough to be removed with pliers.
Position tip of tool, Fig. 23, between crankshaft and seal seat in cylinder block.
Position seal between crankshaft and tip of tool with seal bead contacting tip of tool. Ensure oil seal lip is facing toward front of engine.
Roll seal around crankshaft, using tool as a ``shoehorn'' to protect seal bead from sharp corner of seal seat surface in cylinder block. Tool must remain in position until seal is properly seated with both ends flush with block.
Remove tool, using care not to dislodge seal.
Install new seal into bearing cap with tool as outlined previously.
Install bearing cap with sealant applied to the cap to case interface, Fig. 24. Do not apply sealant to seal ends. Torque rear main bearing cap bolts to specifications.