I hate squirrels too because they not only gnawed a leak into my 1995 fuel line at the elbow at the top of the submerged pump assembly,
but have gnawed through wood at the corners of the house just below the roof.

I was told that squirrels dislike human hair and have put hair at those roof corners.
Coyote hair is disliked too.

I have been told to wrap automobile lines and wires with bronze wool.