I have a '97 Ameriquip Eagle 42 24V towable electric boom lift. Was working fine, and then the other day it started struggling to actuate the arms. The pump would cut out for 2-3 seconds, then start again. Eventually, that 2-3 seconds became 5-10, then 20-30. Now, if the pump turns at all, it turns VERY slowly. Batteries are fully charged, and I also am plugged into 110V. Is there anything else to check before calling the pump bad?