Originally Posted by
batchel9 
When I say he isn't a good dad, I mean he is engaged, patient, motivating to the kids, connects with them, teaches them, etc. When he is sober he is truly great. The problem is when he is not sober.....
It sounds like what you're saying is that he has the POTENTIAL to be a good dad. And that's true of many active alcoholics. They aren't necessarily awful people. But they make lousy partners or parents. Kids do need reliability and stability in their lives. And he will become progressively LESS stable and reliable as his drinking continues.
Kids tend to love their parents no matter what. Even when the parents actually abuse them, they are bonded and love them. So you can't take your kids' LOVE for him as any kind of yardstick for whether it's good for them to be in his care. As the sober, responsible parent here, the onus is on YOU to act in their best interest, whether it makes them (or him) happy in the moment or not.
And if someday he DOES choose sobriety and does the hard work to recover and stay that way, trust me, he will understand why you had to protect the kids. If he continues to drink, well, all bets are off.