Need a temp switch
 

Hello everyone. I'm hoping someone can help me out with locating a temp sensor switch for my rad. It has to be a 2 pin setup to trigger my relay with a 1/8 npt or a 1/4 npt thread. I can't use my heads cause they are already used up and I'm running an LS so no intake locations either. Any leads would be appreciated.
Thanks
Steve

So you already used the driver front and passanger rear location on the head?

Yes I have. The drivers side runs to the computer and pass side runs to my temp gauge. Rad rad has 2 spots that I can use but their 1/4 npt or 1/8 npt.
Tanks are too thin to drill and tap and Im not a fan of the probes.

tap the water pump. Why not use another probe to install it in the radiator? That or use a adapter

What brand of gauge? Full sweep?

My gauges are new vintage USA. I managed to find a sensor from Derale part #16720. I hope this can help someone else.

If one runs to ECM why not have it control output to relay?

Dave

Dave that's a great idea and I thought of that but I would like this fan to come on earlier than the PCM fan. So what I'm trying to do is have a fail safe to keep temps lower by having the fans come on at different temps as well as not having a large load coming on when both fans come on at the same time. I hope that makes sense.

What ECM? Many have two fan output drivers.

Dave

The PCM is a stock LS1 and the problem is the computer is in the trunk with the wiring already concealed in the Howell conduit. Don't wanna run an additional wire all the way from the rear. Way back when I had the harness made I was gonna run the additional fan off a manual switch. I don't wanna worry about forgetting to turn the switch on. So with the rad temp switch it can be controlled and turned on a little earlier.

Steve

Adjustable dual output temperature switch & 1/8 NPT sensor
 

I know this is an old thread but I just saw it so in case this helps someone else with the same problem.

Lingenfelter makes a dual output fan temperature relay controller called the TBRC-001 that you can adjust yourself between 0-350 degrees. It is LPE part # L460220000.

To look at it on our site:
Lingenfelter TBRC-001 adjustable dual independent output temperature fan and relay controller

On LPE's site.

It works with many common temperature sensors from GM, Delphi, Bosch and others, including an 1/8 NPT sensor sold by AEM (and others):

AEM 1/8 NPT sensor, 30-2012

Link to the TBRC-001 instructions (that include a list of the different ECT, IAT, EGT etc sensors it works with).

If you are using an LSx type engine you can also just put another factory 12mm engine coolant sensor in the passenger side cylinder head and control the fan(s) from that sensor. We did that in this video just to show how a similar product (one for controlling variable speed fans) could be connected: