Thermo switches to solve overheating

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I just bought a Borg Warner TFS 545. I was assuming that it was a direct plug in but see that it isn't. I'm assuming that you guys are just cutting off the factory plug, installing new terminals on each of the wires, and plugging them in individually?
 
I believe I used the original o-ring as well , not the one that comes with the borg-warner ( too thick ).
 
ok - so after reading this post, I have an idea, if you want the best of both worlds, do what I just did, go to you local auto parts store buy a $2.99 rocker switch, non lit, and simply wire it between the 2 wires comming off the thermo switch, and mount it in the panel infront of the key switch. Now when you want the factory thermo switch still works like normal, and when your in a high heat situation, simply flip the rocker and the fan comes on manually ! when you begin moving again flip it off, if you ever forget to turn it on the factory switch will still do it automatically, this also works well when your tuining in the driveway, it will never heat up to the red. The reason you dont want a lit switch is beacuse the double ground required to light the switch will blow the fuse on the fan, I found out the hard way !!!
20 minuets an $3 later you running cool !!!!:clapping:
 
ok - so after reading this post, I have an idea, if you want the best of both worlds, do what I just did, go to you local auto parts store buy a $2.99 rocker switch, non lit, and simply wire it between the 2 wires comming off the thermo switch, and mount it in the panel infront of the key switch. Now when you want the factory thermo switch still works like normal, and when your in a high heat situation, simply flip the rocker and the fan comes on manually ! when you begin moving again flip it off, if you ever forget to turn it on the factory switch will still do it automatically, this also works well when your tuining in the driveway, it will never heat up to the red. The reason you dont want a lit switch is beacuse the double ground required to light the switch will blow the fuse on the fan, I found out the hard way !!!
20 minuets an $3 later you running cool !!!!:clapping:


Better known as a manual fan switch.
 
Better known as a manual fan switch.

Not sure if you are wiring it properly. I am using an LED to let me know the fan is on, but I also have the 12VDC line in an ignition controlled supplied voltage. This way the fan cuts off when the ignition is cutoff. My bike NEVER gets over 195F runs at 190 but I am also running an automotive 190F Thermostat.
 
if you just jump the 2 wires on the thermoswitch, it is controlled by the ignition switch too. as for the manual switch comment, its only manual if you want it to be, it still works automatic if you dont . your not cpmmited one way or the other.
 
I have been thinking of this mod because of the Texas heat. I want the switch to only work when the ignition is on and for the automatic function to work as stock so if I forget to turn the switch on, the fan will work when the proper temp is reached. Is there a instructions for this setup available? I was going to buy the eBay one but it is $23 with shipping.

One of my friends has one on his Max but it works whenever the switch is on, even when the ignition is off. Ran his battery down once when he forgot to turn it off. Don't know if the fan still comes on when it gets hot if the switch is off either.
 
One option would be to run one of the switch wires from a p/u coil wire. The other would go to the wire feeding the fan. You can't use the ignition coils since they are always powered regardless if the ignition is firing or not.

Let me do some more thinking about this. Maybe you could use the SCCR.
 
You can't use the SCCR either. What about the gray wire going from the tach to the vboost controller? I think there would only be voltage there if the tach was sending a signal at above 0 rpms?
 
I ran my manual switch through a relay so I could use a mini toggle switch. I pulled the 12V source & ground for the relay from the temp gauge.
 
Great sticky anybody do this with photos for the manual fan switch? Sorry I am not much with electrical stuff.
 
The easiest way to to the manual switch is simply mount your switch in the desired location. Run one wire from one side of the switch to one side of the sending unit (I use a male spade connector and push it in to the back side of the connector so no cutting involved) and then the other side of the switch to the other side of the sender. The sender for the fan is the two wire switch in coolant chamber under the right scoop.

You can also splice each wire in with the existing wires or even use the clamp on type of connectors. I do it this way so there is no power wires to run, if you shut the bike off the fan shuts off (it's easy to forget about it being on), if a wire falls out nothing gets shorted, the wires are very short in length if you put the switch in the screen in front of the scoop or into the same cover that the ignition housing passes through, and the system still operates like stock unless you override it with the fan.

Super easy to do. Takes 2 wires about 1' each (or less) and one switch.

Sean Morley
 
+2 (and many others I have setup) for the manual switch. We have tried the other switches and they all basically leave the fan running all the time when it gets to temp.

The manual works very well and is a cheap install. About $3 and 10 milutes with no coolant loss or wire cutting / splicing involved.


I would like to install this manual switch, is there any install pictures that anyone has posted?
 
No pics ron but when you remove the right scoop. The sender is the larger screwed in unit with 2 contacts. Run one wire to one side and one wire to the other from your 2 pole non-lighted switch (or ignore the third terminal for those types of switches). It's that easy. I usually just use male spade connectors and push them into the backside of the connector right on top of the existing plug (with it plugged in). In this manner if the connector falls out there isn't anything to short out and if you forget to turn off the switch the fan turns off with the key.

Sean
 
hey ron, haven't done it yet but its pretty easy. look at your thermostat. basically u need to make a switch that manually connects those two wires. splice into both of them and connect an ON/OFF switch. ON will manually turn on the fan. OFF will let the thermostat do its work
 
No pics ron but when you remove the right scoop. The sender is the larger screwed in unit with 2 contacts. Run one wire to one side and one wire to the other from your 2 pole non-lighted switch (or ignore the third terminal for those types of switches). It's that easy. I usually just use male spade connectors and push them into the backside of the connector right on top of the existing plug (with it plugged in). In this manner if the connector falls out there isn't anything to short out and if you forget to turn off the switch the fan turns off with the key.

Sean


Sean,

When you say use male spade connectors and push them into the backside of the connector do you mean where I have the red arrow in the picture .. Also does it turn off when you turn your bike off, in case I forget?

thermoswitch.jpg
 
hey ron, haven't done it yet but its pretty easy. look at your thermostat. basically u need to make a switch that manually connects those two wires. splice into both of them and connect an ON/OFF switch. ON will manually turn on the fan. OFF will let the thermostat do its work


Thanks, I think I'd rather do it the way Sean suggested, that way I don't have to cut anything... just waiting for a clearification on where to push the spade connectors in.. I just posted a question to Sean so I'm sure he will reply when he can.

thanks

Ron
 
I soldered all my connections... It's just a contact closure setup. I used automotive wiring with heat shrink covering it the whole way and ran it over the engine using wire ties to hold every thing together and then put the switch in the left head stock cover.
 

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