I posted recently asking how to test the radiator fan. I ended up buying a second hand one from a car breakers. He tested it before I left and it worked, but the fan does not come on. Has this something to do with the thing (sorry don't know the name of it) which is screwed into the engine next to the temp sensor. Or could there be another problem. My son drives the car and says that the temp gauge goes up into the overheat area and then back down a bit. If it was overheating I would have expected to see steam coming out from the bonnet??
Fans are usually (but not always) controlled by a switch in the radiator, not in the head. At their simplest they're just a single action switch which makes contact above a certain temperature. In almost all instances the fan isn't driven directly from this switch but is fed via a relay to bolster the current handling capacity.
In news:E6scf.12648$ snipped-for-privacy@newsfe6-win.ntli.net, Rodders scribed for want of a better word:
Just done mine It was a siezed thermostat How to test Take the connector off the switch (looking into the engine comp from the front, it is bottom right of the radiator) Next the plug connector that came off that, Short the two pins together (best to use a fused bit of wire and with the ignition on, though if you have seen the fan running just use plain wire to short the plug out) If the fan runs then you have either a seized shut thermostat (where it goes into the engine block) or a non working thermal switch, the one in the radiator) Either replace the thermostat £3.50p or check the switch Using an ohm meter get engine hot and switch should close
Actually if you get the engine hot and just feel the bottom hose of the Rad if the top is hot and the bottom is cold then it is the thermostat in the pipe at the engine block that is seized shut. If top and bottom pipes into the Rad are hot then it is a good bet that it is the thermal switch KEEP THE RUBBER RING OFF THE THERMOSTAT as the new one will not have one
Re my on going problems with the radiator fan of my renault 19, I remember reading somewhere that I can use a paper clip to bypass the radiator switch which tells the fan to come on, thus having the fan on at al times. Can someone tell me (in plain English please :-) , how to do this.
In news:LVHef.3335$ snipped-for-privacy@newsfe5-gui.ntli.net, Rodders scribed for want of a better word:
Read my post above "YOU DO READ REPLIES DO YOU NOT" Looking from the front of your car , right hand side of Radiator half way down is the thermal switch Disconnect the plug , (if you know the fan is good ; as you said you had seen it tested ) then using your paper clip with engine running short out the two pins on the plug that came off, (if you have not seen the fan running then use a link of wire with a fuse in it) the fan should run If it does not then the fan motor is duff If it does then it is either the thermal switch or the thermostat (run engine till hot, if top hose is hot and bottom hose is hot then it is the thermal switch screwed into the radiator, if top hose is hot and bottom hose is cold then it is the thermostat inside the top hose where it connects to the engine block) If it is the thermostat replace it but keep the rubber seal off the old one as the new ones come without the seal
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