Club 80-90 Forums

Hi there.

When I am driving my radiator is fine, but when I sit in traffic, the needle goes up, until eventually the red light comes on & starts flashing. If I drive the radiator cools & the needle heads back towards the middle.



Any idea how I prevent the radiator over heating when I'm in traffic? 

Thanks in advance.

Does the fan kick in before the light flashes, you may have a two stage fan so worth checking its function.  If the red light flashes at the stage you mention it does sound like an overheating issue and not a coolant level indication.

Sounds like your fan isn't kicking in. Could be duff relay, fan, thermoswitch or could be a loose connection.

You could remove the thermoswitch from the rad and while its plugged in still sit it in some boiling water see if the fan comes on you should be able to hear the relay click as well. Coolant will escape from rad obviously so make sure you top up/bleed as necessary.

Cooling system may need bleeding and, as already mentioned, fan should kick in so could be an issue with the fan or the thermal switch that is mounted in the radiator.

The indication is of engine temperature not radiator temperature! Have you checked the actual temperature of the radiator and engine?

As mentioned, check coolant levels when cold, header tank full to brim (the one with the Dalek cap), top up tank to full mark (one behind number plate. Run engine up to temperature Remove grill  to get access to radiator and check it all warms up, bleed as necessary. Check fan kicks in (mine normally kicks in between half way and two thirds on temperature gauge, fan then cuts out when hovering around midway. Check system for leaks, if fan not kicking in and radiator hot and temperature gauge high as indicated above, then do checks on fan, plenty of threads on here to show how this is done. 

Thank you everybody.

It’s worth mentioning here , that there is no electrical connection between the engine and the rad fan ,
The only connection between the too is the coolant .
The switch in the side of the radiator is the controlling item .
If you bridge the switch out be aware that the fan is always live , even with the keys in your pocket it will still spin the fan , never put your body parts near the blades , they are not plastic , they will remove your parts !

Any success ??