Hey man I actually played this team not long ago on the ladder. (I was under my main but idk if you remember me)
Anyway something that really struck me was how much of a threat Sand teams are to you. It was pretty simple for me to set up SR, lure Starmie in and then trap it with Tar. Granted, you got Rain Dance up before dying but it was a simple matter to sac something, bring in Tar and bang, Dragonites MultiScale was gone, and Cloyster and Volcarona had there sashs broken. when that was done, Excadrill basically went on to sweep your entire team.
Unfortunately its pretty hard to fix this without you changing the team severely. You could look into Conkeldurr which can pick off LO Adamant Excadrills slightly better than Breloom can as well as deal with stall slightly better I guess. Really tho my main gripe is against the Focus Sash's on Cloyster and Volcarona. Lum on Dragonite instead of leftovers also slightly bugs me but at least Lum has a use against a Sandstorm team. I really suggest you trying out different items on the above pokemon since sash seems a total deadweight against any team with Tyranitar