15-10-2015, 09:04 AM
It may just be dirty or blocked if not in use for some time, try with some of unlocking spray
(30-09-2015, 09:12 AM)brian moffett Wrote: Hi our liftmaster professional 300 gate rams are working automatically fine but we had a power cut recently and needed to open them manually. We unlocked the arms on both sides and turned the black locking mechanism that the key is in but the gates wont open. can you help please. We have tried it in all positions but it just fails to open.