To whack your pud is to
choke the chicken, beat the meat, polish the pole, playing with your magic johnson, arm aerobics, bashing the bishop, be your own best friend,
check the plumbing,
shoot the sheriff, dilly with the willy, drain the sea monster, firing your musket, evacuating tatooine, spank the donkey, to wank, jack off, jerk it, yank it, pull it, eating grapes with a one-armed man, or masturbate.