Thermo-switch mounting locations

[MaineShark]

I need to install a themo-switch to control my electric fans. Actually, I'd like to install two.

I have one location available - the mounting place for the stock auxilliary-fan thermo-switch, in the passenger-side head.

The only other taps into the coolant system that I'm aware of are the one in the driver's-side head, the one in the thermostat housing, and the one in the intake manifold, right next to it. The first is used by the temp guage sender, and the other two are occupied by stock vacuum switches, and I really don't want to start ripping apart those control systems (especially since I'm not sure what they do).

Are there any other taps into the coolant system? If I need to, I can use a switch that pushes into the radiator, but I'd prefer to tap one into the coolant, if I can.

Joe

 

[69MyWay]

Joe,

You can get a piece of pipe and have a threaded bung welded into it to screw your sensor in. Then, split the upper radiator hose, and fuse the pipe in there with the sensor in place.

The other option is drilling and welding another bung on the goose neck/thermostat housing.

I have used the radiator push in switches with complete success now for many years. It is the quickest, easiest alternative.

Summit racing also sells one that you use a twist tie and zip it up to the bottom of the radiator hose. It has two wires, (one for ground, and the other to go to the relay). You can buy them in different temp settings. That is the least invasive approach, fast, quick, and cheap.

 

[MaineShark]

I think I'm just going to replace the heat riser valve with the sensor. That's a 1/2"-14 tap, just like the one in the head.

My problem now is finding switches that fit. There are a number of factory GM fan switches with this thread, but I can't find temp specs on any of them.

There are a few Chrysler sensors that might work, but NAPA says they are all special-order items. I'm hoping to stay with readily-available factory parts, as much as I can, for reliability and ease of repair, if I'm stuck somewhere. And I'd like to stick with GM parts, on general principle (or is that "General principle"? ).

I know a guy at a GM dealership and I'm hoping maybe he can get the specs for me.

Joe