Just bought a 1992 Ford Econoline Van. The power seat, lift and door opener all work. But the door opener needs a nudge to get going.

The door moves out then slides over. It needs manual assistance to move out. Then it slides over on it's own. When I push the button to open the door, the chain bunches up like it can't get any traction to move the door out. Once I give the door a push outward with my hand, the door opener slides the door on it's own.

My mechanic thought the chain was being pinched and a realignment would make it work. But he gave up and said I should take it to a mobility van shop. I hesitate to take it there because I know they will want to sell a new system when it appears it could be repaired. Any ideas?