1984 300 SD

1/ The switch on the thermostat housing is it normally open
when cool

2/ At what temperature will it switch.

3/ Will it turn on the Aux fan when engine goes a higher than safe
temperature.

OK I lied, 4/ Does it have anything to do with the heating
system.

__________________
1984 300SD turbo 126
"My true love"

God made me an atheist and who am I to question His wisdom