You do? Since when? I beat him just fine even in like 630 ilvl gear. Did it on my warlock, did it on my hunter, did it on my fury warrior, and did it on my evoker.
You only need to get him to 50%. Use healer brann, maybe tank brann if you can heal him, and kite if you have to. He wastes a lot of time on abilities and as long as you don’t get clipped by flamethrower and have room to kite him, you can go all day no sweat