So pleased to find this forum. Currently working on 59 MKII with Auto Trans. Having difficulty with the Auxiliary Carburator not working which makes it near impossible to get her running. Looking for methods to determine if TSC is good or if it is the Coolant sending unit.
There is a temperature switch on the intake manifold, and a solenoid at the carb. The switch shorts to ground when the engine is cold (below about 65 Deg C) and goes open as the engine warms up.
If you’re getting battery power at one side of the solenoid, then pull the wire off the switch and earth it - if the solenoid clicks, then your switch is faulty.
Some people wire a manual switch. Getting the screws holding the “Otter” switch out of the Al manifold can be a bear.
its very common to have a switch fitted to over ride the otter (coolant) switch
(check the wiring closely for a hidden switch)
the ASC can easily be removed and tested on the bench, if needed
away from explosive petrol fumes & 12V spark
sometimes the central valve rod sticks in the solenoid