Faulty Parts

I own a 2011 Isuzu 250 Dteq. <br> <br> I recently noticed problems with my original viscous fan-clutch (which was engaged at every start and had trouble disengaging) and therefore purchased a new one from Williams Hunt in Randburg. However, it worked well for a month or so and then it too was engaged most of the time. This is a nuisance, as it sounds like an aeroplane about to take off when driving, it saps the engine power, puts unnecessary strain on the belts and is bad for fuel economy.<br> <br> The above was reported to Williams Hunt Randburg, who asked me to bring it in. They confirmed that it did not disengage, however, I was told that there could be other problems. I was asked to take it back to them for further inspection, after which they reported everything was in order and that the viscous fan-clutch was operating 'normally'.<br> <br> If 'normal' is that it is engaged most of the time, why was I asked to bring it in twice?<br> <br> If normal is that it's engaged most of the time, why spend money on a costly clutch system and not just connect it straight onto the engine? <br> <br> If this is normal, why didn't it do it before?<br> <br> I want my money back or an exchange for a product that works.