Skooter, you mentioned a 1952 pickup and if you have the 1952 235 you'd be right...it wasn't designed for the neoprene seal. Doesn't mean you can't use one. You can do that but you may have to shim underneath it to ensure it makes a good seal with the surface on the crank. Or likewise I suppose the groove might have been machined in a fashion where it is too shallow and might press the neoprene seal too firmly against the crank (though I've never seen that yet). Seeing you may have a 1952 235 is why I came back and added that idea in my earlier post. By far the best way to handle this is to machine the block to accept a one-piece seal (like the one used on the harmonic balancer). Jerry has built a jig to allow that to be done, but you have to have or have access to a Van Norman (or similar) boring bar. Good luck!
