Eugene Levys Mentor?
Eugene Levys played the obsessed professor, and we see his old mentor
that guys voice sounded like Id heard it many cartoons.
Who was he and did he also do cartoon voices?
That was the late, great Howard Morris, who played Ernest T. Bass in The Andy Griffith Show when Ron Howard was a child actor.
Like you said, Morris' voice was in all sorts of cartoons--The Archie Show, Atom Ant, The Flintstones, Beetle Bailey, Sabrina The Teenage Witch, etc.