Grab him by the back of the neck & walk him out the door.
When I was a senior in high school, my mother went to TX. to take care of her father & his wife, my father had gone back to sea. So, my father comes back from a sea, my older step sister of course has a few projects for him at her house, feeds him plenty to drink. Well, my dad always told me that when I was 18, if he ever thought that I was ***** up, he would take me outside & beat the crap out of me (not in those words). Now, my dad spent his entire adult career after W.W.II in a union, retiring as the agent for the SE, born & raised in Brooklyn, depression era, went back to sea at age 60 as a Merchant seaman, so he was more than able to back up any threat that he made
Well after a few drinks thanks to my evil step sister, he checked my tool box for a few tools he needed (these were tools I bought with money I earned doing odd jobs) and got pissed that they were at my Aunts house (I blew the rear end out of my Datsun pick up & fixed it at a garage my Aunt had) and he couldn't reach them.
Well, I could tell that he was drunk, and & pissed off (my older brother always screwed up, tossed away a Football scholarship,smart, talented, everything that I wasn't, plus, he kept getting arrested (something I never did), so every time he did, I paid for it. This time, I was over 18, my dad was pissed (even though I didn't do anything) so I called a buddy, we loaded everything I owned into mine & his trucks. The very first thing my dad did was changed the locks in the house I grew up in, 2nd was call my mother & tell her that I showed him that I was a man & left home and if he caught me there, he would have me arrested for trespassing (I told you I grew up with tough love) as I was still in high school right across the street from the house I grew up in. So, at 25, show him the door. If I could make it, and 10 years later my daD finially talked to me again, there is no reason that he can't go out & make something of himself.