Adding 2nd water temp sensor

[duragg]

Need a 2nd water temp sensor / sender for my eFans.

I have the stock temp pickup in the front of the T-stat housing.

 

Where ideally would one mount the 2nd pickup?

There are 2 other unused bungs I see in the T-stat housing, both face drivers side if I recall.

One on top, one on bottom.

 

Anything else to consider in this area?
Tj

[OldAndyAndTheSea]

The directions that came with my electric cooling fan gave me two options.

 

first, if I decided to use that brass probe, they'd recommend putting the probe as close to the inlet to the radiator as physically possible.

 

The second option, which I opted for, was a 3/8 npt adapter, which also came with the fan. I tapped the housing for 3/8 npt and mounted it in the housing, as you were thinking.  (bottom right of the thermostat housing)

 

 

 

I'd just be really careful tapping the housing if you decide to go this route, as they are pretty brittle sometimes, and one slip of a drill can pop a hole in the side of one pretty quick. Ask me how I know

Edited April 2, 2013 by OldAndyAndTheSea

[duragg]

Splendid.

I must have a different style housing: 

 

 

Guess the ideal is the lower hole, out of the engine, prior to the T-stat.

[motomanmike]

Not sure whether you could or would want adopt one or not but wasn't' the stock 280zx injector cooling fan temp sensor in the heater hose with a 2 wire set up? Might be able to use an old stock one in the hose easily to turn the fan on? If not use a 280zx style thermostat housing with all the spots on it you could tap quite a few sensors in if needed.

Edited April 2, 2013 by motomanmike

[Tony D]

Radiator Hose Mounting for both?

 

I used Suzuki Switches on Suzuki Bungs in the bottom of my lower radiator tank. Protected and easily done when recoring. Just some brass fittings the shop had and out I went to find appropriate switches.

[duragg]

Well I was trying to use the fancy BMW dual-temp switch which is supposed to go Stage 1 at 80c and Stage 2 at 90.

It has M14x1.5mm threads. 

 

Tony what do you mean hose mounting?  You mean one of the bulbs that goes into the hose and water stream?

 

I have now 3 distinct kits in my hand

1)  Push into the radiator kind which is even too hokey for my bad taste,

2)  Bulb in radiator to a variable controller kit which still seems kinda hokey,

3)  Threaded sensor which goes into the T-stat housing or the block somewhere.

 

Like all simple things there are 500 options and 15 setbacks.

Example, the URO BMW 2 temp switch marked 80/90 is actually kicking on at 90/100. 

 

I am thinking at the hottest temp spot-the Tstat housing is still the best location if I can get a temp sensor that works as it should.

[Tony D]

No, there is a fitting that replaces a 4" section of hose, and you put your sensors in there, screwed in just like in he housing or rad tank!

[duragg]

Thats a neat idea. 

Spin up a section of tube and weld some bungs in it for all the sensors a man could want.

[josh817]

I am having the same dilema as well, trying to find thread sizes and a spot to put two sensors (one for a gauge the other for MS). Then I realized.... what a dummy, can't I just connect two wires to the sensor and send them to whatever it is I need? Maybe not that easy, I haven't looked into it too hard.

[duragg]

Some sensors sending load or resistance, others binary (more than 160f / lower).

I suspect something like MS is expecting a clean signal, any noise cpild make it angry.

Especially for a variable signal, go dedicated.

[Tony D]

Thats a neat idea. 

Spin up a section of tube and weld some bungs in it for all the sensors a man could want.

They sell them prefab, my original sensor location was using two-pin sensors (key here!)

If you plan on using one-pin sensors that depend on a ground circuit through physical connection to the engine (like the stock gauge sensor) then provision a grounding stud or screw hole to run a 14 gauge wire back to something on the block or chassis!