If you mean on the outside of the snout that goes into the engine, that's wear from where the timing covers seal runs. Get a speedi-sleeve to repair that. I think they're available from RockAuto (you'll need the engine and probably what it came from to get the right size.)
Last edited by klhansen; 09/20/20238:47 PM. Reason: added pic
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
If you don't want to order from rockauto, you can use the part numbers/manufacturer info to go to your local FLAPS to purchase this commonly available item.
Dan
~ Dan 1951 Chevy 3 window 3100 Follow this story in the DITY Gallery "My Grandpa Carl's Truck and How it Became Mine" 1966 Chevelle (Wife's Hot Rod) | 2013 Chevy Silverado (Current daily driver) US Army MSG Retired (1977-1998) | Com Fac Maint Lead Tech Retired (1998-2021)