1994 3VZE 4WD Automatic. About 6 months ago I started to do a head gasket replacement. 6 months later I have the gasket installed, new water pump, new oil pump, new vacuum lines, etc, etc. I have new radiator to go in as well and I am going to add an electric fan. I know of a few ways to install temperature probes for the varying fan controls but I am determined to install a regular brass, screw into the block type temp switch. My setup will began with this basic on/off, to ground switch.

I need advice from someone who has had success with using this type of switch. I have the factory manuals for my 4runner and know I can unscrew my currently unused TVV sensor in the coolant temperature manifold at rear of engine, and their is also a currently unused COOLANT TEMPERATURE SWITCH that shuts the A/C screwed into this sensor block as well.

I even thought about using the COOLANT TEMPERATURE SWITCH to power a relay for an electric fan but I do not know the spec on the switch. I also do not know the thread/diameter of these sensors, any info much appreciated.

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