Good point about main bearing clearance. If the crankshaft is bouncing up and down with excessive clearance, it will hammer the seal away from the shaft and allow leakage. The rubber lip seal might work better with some wobble at the shaft, but it's more prone to wear a groove into the sealing surface. The rope seal, installed properly with a minimum-clearance main bearing is my first choice.
Jerry

Last edited by Hotrod Lincoln; 02/28/2011 10:07 PM.
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