Cooling system

[vinderliker]

In another thread re Luke's Passat I made mention of cooling problems with the Little Beastie. The switch for the radiator fan is kaputt and I have had to loop the wires so as it runs full time. It only gets hot at traffic lights and in traffic. Does anyone have any ideas what may be the cause for the car to heat up so quick?

[gtimk5]

Because you have no air flowing through the radiator when stationary, it will heat up. Thermo fan switches are relatively inexpensive. I am sure CVCC would keep them in stock. Always run the thermostat in the car to, otherwise the cooling system gets confused as to which way to pump the coolant!!!
Cheers, Andrew

[76Passat]

Since you've got to drain the radiator anyway when you change the thermoswitch, it might be worth reverse flushing the radiator (eg take hoses off it and blast cr@p out of it with garden hose from the bottom) and check that it's not obstructed. Mick Motors in Brisbane have the thermoswitches I think I got one there a couple of years ago.

[Jmac]

Back flushing is good but the best way is get it sent away to be done, best results and have it pressure tested then too for piece of mind. No harm fitting a stat as well. This is a very common overlooked item. The biggest problem the rads had was that the switch is at the bottom of the rad and all the gunge falls to the bottom thus the switch doesnt get the chance to heat up eevn though the sytem reqs the fans if that makes sense. had this happen heaps of times.
Good luck