The 74-year-old owner of a car dealership chased off an armed robber with a weed trimmer, whacking him in the behind after the gunman menaced, “Old man, I’ve got you now.”

The robber showed up at Oran McGlamry’s dealership Thursday with a .38-caliber pistol, Police Chief James Vick said.

McGlamry, forced to give up his wallet in a holdup Monday, rushed the gunman with his humming weed trimmer. The surprised robber turned to run and fell. That’s when McGlamry kicked his trimmer into full throttle and whacked him in the buttocks, Vick said.

The robber ran away but sheriff’s deputies found him.

“I was just trying to do what any other man would have done to protect his business, his wife and his life,” McGlamry said Friday.

Jason Gordon, 17, was charged with armed robbery, aggravated assault, carrying a concealed weapon and carrying a pistol without a license, police said.

Gordon had two cuts in the seat of his pants. “I’m sure it stung pretty good,” Vick said.

Vick said the robber told McGlamry, “Old man, I’ve got you now.” McGlamry said: “No you don’t.”

Gordon and another teen robbed McGlamry on Monday while he was showing them a car, Vick said.