Laminator not rolling - is there anything else I can do?

My laminator rollers have stopped working. I have opened it up and they will turn for about a quarter of a turn but then they seem to stick and the motor just clicks. If I give them a nudge they start again but stop in about another quarter turn. The grease seems sticky. I have tried lube oil but that has not helped. I there anything else I can do?
Rexel LH240 (ancient)