that's a steel keel right?
what are you using to protect it? reason I ask is the Oday I looked at a while back, the iron keel was in amazing shape due to the , what I can only describe as road tar, that had been applied and not touched in years.
Hopefully the old owner still frequents this forum...
Looking at the routing of the openings, I can see burn marks telling me your bit is getting a little blunt! let me know what type/size you are using, I can probable spare one of the many hundred I have ;)