lazy leccy hood

The electric hood on my 92 rivage has become very lazy. It's comes down on the switch but will not come back up. I have to turn the hydraulic pump to manual and pull it back by hand.
Any ideas on the problem and how to fix?
I've taken out and cleaned the actual switch to no
 avail. Thanks

Have you looked to see that there is enough fluid in the system?

it may be the impeller on the pump has gone, dependign how bad it is you can sometimes repair with a strip of metal and aldrite. i think kits were avaialble at one point? otherwise the mk3 pump impeller may fit?