Getting things done TWICE and for all! Electric Fan Wiring take 2

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BMW 2002 dual water neck,


So I just realized today that I have a very definite pattern to doing upgrades and repairs on the car. I do them twice. I usually will spend lots of time researching the upgrade, then I will get all the parts I THINK I need to do the job, then I do it. I get it working, and then I go back after I have had the system installed for a while, fix the quirks and polish it all up. This week it was the electric fan. It was done last september the first time. I had a custom pipe made for the temp switch to turn the fan on and off. In newer cars this is in the radiator. I didnt want to modify my radiator for the switch because what if I am driving on a trip and need to find a replacement? I dont want to add to that finding a place that can competently drill a hole in the radiator for the fan switch. The custom pipe worked fine, but was a bit ugly. There is another part that is a similar concept sold from Ireland Engineering which simply is a pipe you put the temp switch in. What I didnt like about my custom pipe was that it didnt look factory. In all my car builds, I am VERY big on using as many factory parts as I can. Also if I am stranded somewhere and need a fan switch…I think I can go to any Pep Boys or Kragens or whatever and get an 80’s BMW temp switch. The custom pipe I had used a generic SPAL switch which had different SAE threads. The BMW is all metric so I may find a domestic car that had a similar size, but again…I dont want to have to hunt that down or be in the middle of nowhere waiting for a SPAL fan switch. So in my research I found that 318i’s and even 2002Tii’s had a water neck with TWO places for sensors. Since BMW is so consistent, I was able to take an off the shelf fan switch plug it into the water neck, in one port, then put the temp gauge sender in the other and BAM, I had a factory looking and functioning fan switch configuration. I then used all the stock hoses, another plus, no need for custom lengths. Wired the switch using the same two wires from the old setup and its an EASY solution that looks great and works great! So here is for doing things TWICE and for all! Here is a pic of the old custom pipe setup and the new pipe setup as well.

The added bonus is I now have the ability to use different temp switches since BMW has 3 they use in their cars. I chose an 86 degree switch which was in the middle. There is an 80 an a 91. The 86 comes on just a tad bit too soon, and stays on to long for my taste. I will keep it a few days though as it keeps the car running very cool and maybe I’ll keep it. I do plan on trying the 91. That one may be just about perfect. The SPAL came in 2 temps, 185 F (85 C) and 195 F (90.5 C). I had the 195 in mine. It seemed to come on and go off ok. Lately though once it came on, it stayed on until I stopped the car, then it would stop and if it was cool enough wouldnt come back on. I think it was a stuck switch since thats the only thing I really swapped out and now it works far more reliably.

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