My Hotpoint Aquarius DWF 31. has stopped completing its cycle, leaving dirty water in the bottom. I've tried running different cycles with the same problem occuring. The Pre Wash (no heat) seems to run hot. The pump grunts on start up but I've checked the impeller which seems to run freely albeit with a resistance then overrun which I'm assuming is part of a clutch type burnout protection. I'm thinking maybe knackered pump or programmer. Is it worth repairing?