fan thermal switch

[betaveloce]

Hi all,

I have a 1981 Beta Spider 1.6 which had some cooling issues. Therefore I recently installed a new radatior and a new thermostat, but now I noticed that the fan does not start automatically. I do have a manual override switch, but still I would like it also to work as it should. But before I try to find or order a new thermal switch, I would like to be sure that the problem lies there and not for exemple in the fusebox...

Now my question: my Haynes manual says: 'Assuming that the fuse is all right and the fan still does not work, then disconnect the wires from the thermal switch in the bottom of the radiator and connect them together.'

However, there are three wires (the short one, the one that goes to the earthing point and the one that disappears in the wiring loom)... which ones should I connect 

[Thotos]

the short one, the one that goes to the earthing point and the one that disappears in the wiring loom)... which ones should I connect 

Presumably by "one that goes to the earthing point" you mean a wire that's connected to an earthing ring round the switch? Then it's the other two wires you need to connect together; it should be the two wires connected to tabs on the back of the switch.

[betaveloce]

the short one, the one that goes to the earthing point and the one that disappears in the wiring loom)... which ones should I connect 

Presumably by "one that goes to the earthing point" you mean a wire that's connected to an earthing ring round the switch? Then it's the other two wires you need to connect together; it should be the two wires connected to tabs on the back of the switch.

Hi Thotos, thanks for your response.

in my probably a bit confusing explanation it's "the short one" which is connected to the earthing ring round the switch

with "the one that goes to the earthing point" I meant the one that goes to the left hand wing. So should I connect that one with the one that dissapears in the wiring loom? Isn't the one a negative and the other one a positive...?

[betaveloce]

So should I connect that one with the one that dissapears in the wiring loom? Isn't the one a negative and the other one a positive...?

update: I did this and then the fan works, so I think I can safely conclude that the thermal switch is faulty. Will try to source one locally or otherwise order one from Betaboyz

thanks for reading

[Thotos]

You've obviously sorted this out now; sorry for the delay in getting back to you. But yes, ignore the one to the earthing ring and connect the other two together. There's a positive wire to the fan and the fan's negative wire gets connected to the chassis via the switch.

These switches are quite easy to get hold of as they fit many cars not just Lancias.

[betaveloce]

You've obviously sorted this out now; sorry for the delay in getting back to you. But yes, ignore the one to the earthing ring and connect the other two together. There's a positive wire to the fan and the fan's negative wire gets connected to the chassis via the switch.

These switches are quite easy to get hold of as they fit many cars not just Lancias.

Thanks Thotos! Update: I found a switch that fits (box says it's for an Alfa 145/146/155), off course I had to change the wiring, but when I let the car warm up on my driveway, the fan cut in nicely. However, after that I had a long drive on the motorway and all was looking very nice, but the moment I got in city traffic, the temperature gauge moved all the way to the right again, and, thinking the fan wasn't working again, I used my manual override switch, but this had almost no effect and after I had let the engine cool down, the expansion tank was empty again... I think there is something seriously wrong (the pressure in the cooling system seems abnormally high)  
I'm going to try to take the car to the garage one of these days to have some tests done!

[Neil-yaj396]

Sounds like the head gasket has gone!

[MattNoVAT]

Or the impeller on the water pump has failed. 

Is water boiling out the expansion tank breather tube our is it just disappearing?  If it's just disappearing then as Neil says it could be head gasket failure.

[betaveloce]

Sounds like the head gasket has gone!

Or the impeller on the water pump has failed.  

Is water boiling out the expansion tank breather tube our is it just disappearing?  If it's just disappearing then as Neil says it could be head gasket failure.

I was thinking more and more in that direction too  

I replaced the water pump with a new one a year ago, so - normally - that should be fine, and yes, as far as I can tell, the water is just disappearing. It's just strange that oil and water still look normal and there is no abnormal exhaust smoke either...

Oh well, on the positive side, maybe it will be a good opportunity to take care of the recent oil leak and a few other things while I'm at it  

[betaveloce]

it's absolutely certain the head gasket 

I just checked the oil again and although this looked okay before it's last drive, it's now the famous mayonaise

well, it least that saves me a trip to the workshop for a diagnosis 

thanks everyone!

[MattNoVAT]

Yep, if there's choccy milkshake in there then it's the head gasket, sadly.

[rossocorsa]

as an MG TF owner and so well aware of HGF can I just say it is hardly the end of the world and tbh not that big a deal I'm sure it can easily be sorted and for not too many pennies

[betaveloce]

as an MG TF owner and so well aware of HGF can I just say it is hardly the end of the world and tbh not that big a deal I'm sure it can easily be sorted and for not too many pennies

you're absolutely right that it's not the end of the world, but, although I try to do the work on my cars myself as much as possible, I am one of those who enjoy driving them more than working on them

anyway, I think I'm going to leave this one sitting for a while and first get the coupé that I'm working on, back on the road. With a summer like this year, the added value of a spider is limited anyway 

[rossocorsa]

I am one of those who enjoy driving them more than working on them

actually I am the same I just somehow end up lumbering myself with 'projects' and because I get less than enthusiastic the latest has been limping along for almost 10 years.