Definately change the water pump i have a Golf and sister has a Sharan the drive on the water pump is plastic and glued on after a few years the glue gives up and the belt still turns the water pump pulley but not the internals leading to overheating problems but no water loss
Pete
The plastic cog which propells the water in come cases is metal (have seen this on earlier models but the later after market parts are usually plastic) is what gives up due to bearing failure.
Grr I hate Sharans... N/S front headlamp can be reached JUST through the panel in the arch, to change a light bulb on the O/S/F you have to remove the air box and surronding parts... Complete waste of time!