Cooling fan switch

OldFoggey · #1 (**permalink**) 12-07-2013, 05:15 PM

Today I noticed that the cooling fan wasn't kicking in a 90 degrees as it should. I used the manual switch to turn the fan on and bring the temp back down. When I got home I placed a jumper wire on the two fan wires at the switch to verify that there was voltage at the switch and wiring was OK. The fan came right on. I looked on-line and there's many different ones available. I see many that have appear to be the same on/off temps so I assume that most of the differences are physical designs of the terminals and the threads.

Has anyone replaced the switch with a non-OEM one? If so do you remember how you cross referenced it to match an over the counter one?

Thanks........Don

Karl Bebout · #2 (**permalink**) 12-07-2013, 08:05 PM

Why not just run the fan when ever the ignition is hot? That way, you don't have to worry about a thermo switch or have to remember to turn the fan on or off. I'd recommend running a relay, if you don't already have one. A universal 30a relay can be picked up for less than $10 and are simple to install. Justa thought.

Rick Parker · #3 (**permalink**) 12-07-2013, 09:48 PM

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Here is a link for a high quality brand http://www.ebay.com/sch/i.html?_trks...at=0&_from=R40
They use a 22 mm thread diameter. I welded the bung (mid RH tank) It could also be put into a short length of aluminum tubing and inserted with clamps into the lower hose run. The one I use closes (fan on) at around 195 and opens (fan off) at about 182, these are estimates. If you choose one of these you may need to do some temprature chart conversions as they are generally marked in Celcius values. Use this or any other Thermo switch to close the circut for a relay that is hot wired to the fan. Do not allow it to carry the current for the fan directly.

OldFoggey · #4 (**permalink**) 12-08-2013, 09:14 AM

Thanks for the replies..........

Rick, I already have a switch factory installed but I'm not sure what thread size it is without draining the radiator to pull it out. I was hoping that some other BackDraft owner might have changed theirs and remembers something about it. I can order a replacement from BackDraft but they are fairly expensive at $38 plus shipping and the wait.

Karl, it seems like having the fan run anytime the ignition is on would be putting unnecessary wear on the fan. Since the majority of my driving time in highway I don't think my fan runs less than 5% of the total time the car is running. I would much rather have it just run as needed.

Thanks..........Don

redmt · #5 (**permalink**) 12-08-2013, 09:59 AM

Finishline has a couple of fan switches. There is an adjustable with a probe for the radiator fins.

750hp · #6 (**permalink**) 12-09-2013, 06:00 AM

You could leave the faulty one in place and look at something like the BE COOL range if thermostat switches that screw into your intake manifold. They make a number of temperature switching options. I have one that comes on at 195F and goes off at 185F. The fan switches on and off exactly as per the gauge readings.

My only preference would be to bump the "off" temp up to 190 as it sometimes takes a few miles of highway driving to hit 180 and switch off the fan. It's annoying sometimes to see the temp hovering at 182 or 183 for miles on the highway with the fan running...

madmaxx · #7 (**permalink**) 12-09-2013, 06:10 AM

Stock item at napa for $15.00 bucks. Call casburn or remove yours and take it down their and match it up. You can get different temperature settings.

Tim Parker · #8 (**permalink**) 12-09-2013, 07:00 PM

I replaced the factory switch on my car BDR 1220 which failed closed. The car was delivered new to me June 2013. Fan ran all the time even when ignition was off. The correct replacement is a Beck/Arnley Thermo Fan Switch part no. 201-0809 comes on at 92 deg C or 198 F and cuts off at 87 deg C or 188 F. This part can be purchased at Advance Auto for about $25.

Rick Parker · #9 (**permalink**) 12-09-2013, 07:25 PM

These are stocking items at good part houses such as Napa or Orielly's.

PLDRIVE · #10 (**permalink**) 12-09-2013, 07:52 PM

http://www.summitracing.com/parts/der-16749/overview/

These work great. Had one for 3 years.

OldFoggey · #11 (**permalink**) 12-10-2013, 08:45 PM

Thanks Tim, Rick and PL. I'll stop by Advanced Auto tomorrow and pick up one to swap out this weekend. Tim, mine has worked flawlessly up until about a month ago when after the fan kicked on it wouldn't shut off for about 15 minutes after the car was shut off. Then it started where the fan would never turn on.

Thanks again........Don

mln385 · #12 (**permalink**) 12-11-2013, 05:43 AM

Quote:

Originally Posted by OldFoggey

Thanks Tim, Rick and PL. I'll stop by Advanced Auto tomorrow and pick up one to swap out this weekend. Tim, mine has worked flawlessly up until about a month ago when after the fan kicked on it wouldn't shut off for about 15 minutes after the car was shut off. Then it started where the fan would never turn on.

Thanks again........Don

Just an FYI I think BDR put a timer in around your build time of a fan delay until cool down.