Hi, I just removed the pump from the vehicle. Popped off the back cover and sprayed insides with wD40. Left it for 30 mins and then connected pump up to 5amp trickle charger. The pump ran ok so refitted to the car and cruised along.

 

Thanks ,

The bearings being freed up with WD - 40 or a penetrating oil may need to be replaced as a second step afterward with a more substantial and non evapoative oil like a electric motor oil or a 4 in 1 brand oil that would last longer in long term service