Q: I need to drop the rear of my 1979 351 W crankshaft to replace a rear main seal, but how much can I drop it?

asked by on January 18, 2018

I am replaceing a rope type oil seal in a 1979 351 W Ford V8. Instructions say to drop the rear of the crank a little bit to get the upper half of the seal into the groove in the block. This is necessary as the NOS asbestos seal (upper half) will not feed in using a sneaky Pete tool to pull it through. How much can I drop the rear of the crank without ruining the front main seal?

Once you remove the rear bearing cap and loosen the other caps by one to two turns on the bolts should be just enough to lower the crank to get out the rear seal.

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