Originally Posted by joe apple
I believe you need to use some sealant on the flywheel bolts to keep crankcase oil from leaking out.

Joe
What size/year engine?

I do not recall reading that instruction in a Shop Manual for a 216/235/261?
http://chevy.oldcarmanualproject.com/shop/1948_51truck/51ctsm0634.htm

We'll hear from a pro (hopefully).