If the pump stops and starts, the 12V breaker that supplies power to the hydraulic pump may be tired (or as Cookie suggested, you might have a bind or lack of lubrication, in which case the pump would try to draw more power and trip the breaker). I think the breaker auto-resets after a second or two.
It's probably a 50 Amp 12V auto-reset circuit breaker available at any auto parts store. With shore power and battery disconnected, you can replace it in a minute or two. They're very inexpensive.
Here's a link to one sold by Amazon.
I've attached a better picture. Also, a picture of the row of 12V circuit breakers usually located next to the battery. Trace the wires from the hydraulic pump to find the breaker in question.
Lubricating the slides would be a good idea even if the breaker fixes the problem.