I have a 2001 Load Rite, double axle trailer with surge brakes (Drum)on one axle. One wheel keeps locking up going forward. I opened the bleeder screw thinking it might be a bad master cylinder but that doesn't free it. If i rotate it backwards by hand it works fine but when i switch to forward again it will go a couple of turns and lock up again. Bad actuator? I haven't had much experience with surge breaks so I thought I would look for a little info before I take off the drum so I might have an idea what to look for. Thanks, Rick