Radiator Fan Switch

[GOPAPA]

I got the fan switch today ..

Can anyone tell me if I have to drain my Radiator first to install the switch . Fiat Radiator that is ,,,LOL

Or does it not go into the water and only into a cavity ( lost for a better discription ) and draw radiant heat from the metal of the radiator to activate the switch??

Heres a picture of the switch . Papa

[adrians]

Yes, water will pour out when you remove the old switch ... so drain it first.

Also a quick word of warning, those switch with the leads may not be exactly the same temperature range as the original one, so the coolant will get hotter prior to the fan operating.

I would check the switch with a pot of boiling water and a thermometer and compare it to the old one, if still operative.

I found out by experience !

[GOPAPA]

Yes, water will pour out when you remove the old switch ... so drain it first.

Also a quick word of warning, those switch with the leads may not be exactly the same temperature range as the original one, so the coolant will get hotter prior to the fan operating.

I would check the switch with a pot of boiling water and a thermometer and compare it to the old one, if still operative.

I found out by experience !

Hope you don't mind a long reply question..Boiling water boils at 212 degrees so is this the degrees that the switch is designed to come on .?

And are you saying that the original didn't have leads ? Either some one put a new one in some time back or the one that is in there now is the original and it has leads.

I suppose I could check it this way .
Get a pot of water and put it on a hot plate and put the hot plate close to the car where I can hook the switch submered into the pot of water. ( of course only the part that is supposed to be submerged) then hook some longer wires up between the fan motor and the switch .. start heating the water and watching the thermostat so when it makes the fan motor run then that would be the degrees that the switch is set at to work .
I am open to all ideas if this is more than is needed. thanks by the way ,,papa

[rlux4]

If you have a candy thermometer and an ohmeter, heat the water up and see what temp. the switch activates. It should come on at around 190° more or less. Testing it this way will tell you at what temp. it does come on.
Ron

[GOPAPA]

If you have a candy thermometer and an ohmeter, heat the water up and see what temp. the switch activates. It should come on at around 190° more or less. Testing it this way will tell you at what temp. it does come on.
Ron

WE have a canning thermometer to prove out the temp that it activates .. good idea ,, thx papa

[rlux4]

My pleasure Papa, just send some peaches next canning season.
Ron

[adrians]

Gopapa,
I tested my two switches by heating them in water on the stove and having a multimeter hooked up to it - with the meter set of continuity ( so it beeps when the switch circuit closes ), oh and a thermometer to measure the water temperature.

The switch with no leads ( only spade terminals ) my original switch closed ( actived ) at a lower temperature than the new replacement switch ( with leads - like your photo ). These switches are sold as Spider switches but are used in X19 and Regata's - so I discovered.

So just be aware that the car may run a little hotter prior to the fan cutting in.

[So Cal Mark]

the later Spiders, 79 and up, used the switches with the bullet type leads

[manoa matt]

If all your caps are on tight you should be able to remove and install the switch without much water comming out. I've done it with the drain plug, had it out for several minutes and only a few drops came out. Air must get in at the top for water to come out at the bottom.

Remember the old trick of placing a piece of paper over a brimming full glass of water and turning it upside down. The paper sticks and the water does not fall out.

Good to know about the different temps of the different designs, one question though: Some fiat owners including Mr. Croft recommend running with a slightly cooler thermostat, whould'nt you also need a cooler fan switch? Otherwise the fan wouldn't come on, right?