Hello,

Jaguar, 1976, V12, Pre-He engine.
we will put new thermostats ( 82 C), the question is about switch, How much C have to be this switch? The original one is broken and dont have number on it. BR, Stan

 

Do you mean number 12?

 

Yes, number 12 on the scheme,
I believe it have to be in relation with temp of the thermostat.
BR Stan

 

Stan,

All the switch is doing is sending a reading that indicates the temp of the coolant behind it. It's not linked to which thermostat you're fitting.

Cheers

Paul

 

Stan
The switch is a 22mm fan thermostatic switch. It switches on the electric auxiliary radiator fan when the temperature goes above a certain level. They are readily available. On the HE engine it switches on and off at 85° C. I am not sure about the switching temp on the pre HE. Grant will tell us shortly!

 

Hello,

Ok, but our engine has visco fan.
I can’t understand purpose of this switch.
Maybe it is related to electric clima fan?

 

Stan,

Greg has answered as only he can.

All my PreHE had the same 85C temp reading that I remember???.

It is solely to operate the LH small electric fan.

My cars had 88c stats when first arriving, and all were fitted with 82c stats withing the 1st week.

 

Stan
This is the auxiliary electrical fan:


It is switched on and off by the thermostatic switch we are discussing. In addition, when the air conditioning compressor is working, this fan may be activated too. Some models had this feature, some did not.

 

Clear enough, thank you,
you are very helpful as usual.