Electric fan

[Rut]

When installing the temp sensor for an electric fan is it best to place it in the head or radiator? I have the 5/8x18 adapter in both and will use one for the fan and the other for the gauge.
Thanks, Rut

 

[OopsClunkThud]

switch for the fan in the radiator, temp gauge in the head.

 

[Trevor Jessie]

I agree with Patrick. That is how mine has been set up for several years now.

 

[RickB]

Also how mine is set up, with a variable temperature control so I can set where I want the relay to latch.

 

[Rut]

Thanks guys! Rick, what parts did you use for the sending unit, control switch, and fan? My local auto parts/machine shop ordered a 'sensor' for me yesterday to check fit and I want to make sure I get the correct one.
Rut

 

[nomad]

Just for thought, I would consider fitting the temp sensor for the fan in the bottom radiator hose. Recently cooked my son's Datsun pickup using a temp sensor at the top of the radiator. The rad had a small leak that he wasn't aware of and once the radiator coolant level got low the fan didn't run! If the sensor had been in the bottom hose that would not have been a problem. That's where the factory's locate them.

Kurt.

 

[Jim_Gruber]

Yes but how does one get a sensor inside of the radiator hose, this sounds like and interesting fix?

 

[OopsClunkThud]

they make them to be spliced into the hose.

https://www.iemotorsport.com/bmw/2002-cooling/hoseadapter.html

 

[Jim_Gruber]

Oh that is absolutely a trick piece. And only $12.00. Why would you want to try and get something to fit and seal in a 50 y.o. + radiator. I'm impressed.

 

[OopsClunkThud]

verify that the size will fit the hose for the spridget before ordering, was just pointing out that such a thing is out there. I have a similar item on our BMW 2002.

 

[dklawson]

Those temperature sender adapters are sold by many vendors on eBay in different sizes. I like the part in the link above since the part is black. Most of the eBay parts are either the red or blue anodized coating common on AN fittings. I believe you will find that the tap for the sender is also available in a couple of different sizes.

Keep in the back of your mind that many mechanical temp gauges use 5/8-18 threads. You probably don't want that size for your fan switch since there are not a lot of compression fittings and/or adapters for that size. I anticipate you will want either a hose adapter that is tapped 1/4- or 1/8-NPT depending on the type of fan switch you have.

 

[nomad]

Need to remember also that that is the cool side of the radiator so you may want the temp settings for your sender to be lower.

Kurt.