I have 4 acuspot 250 mark 1's and 2 of them have started giving me problems:
Best way to describe it is when switched on they go through test and go to zero position then when I try to run them they start to judder..like the pan motor is juddering and not going smoothly and making a grinding noise like slipping sounds....I disconnected them from the DMX controller and cables and ran them stand alone but they still do it......I cannot see any gears anywhere to lubricate or dismantle or anything - anyone know of this failure/problem and suggestions?

Call our service dept please. this is mainly a issue for them.
Sincerely,

It sounds like the belts are slipping on the unit. I reccomend sending the unit back to ADJ for service since these light are very tough to diagnose. Call ADJ Service at 800-322-6337 to obtain an RA# with shipping instructions, The Estimate is only $25.00