A Long Island mob goon pleaded guilty Friday to threatening to beat up a 71-year-old man over an unpaid loan at the behest of a Luchese family captain.

Michael Capra, 52, admitted he tried shaking down the elderly victim in 2010, as he copped to conspiracy to commit extortion charges.

“I did threaten him with physical force if the debt was not paid,” he told Brooklyn federal court Judge Ann Donnelly.

When prosecutors asked if he was collecting money specifically owed to Luchese capo Carmine Avellino, he said, “I really don’t have any idea.”

Avellino was caught on wiretaps allegedly ordering Capra to assault the old man and another victim over a $100,000 loan. Michael’s lawyer declined to comment.