Intercooler Fan
Information on adding a fan to the intercooler on a Toyota Celica GT-Four ST185
Protector Clips
First you will need to remove the intercooler protector. To do this locate the three 10mm bolts holding it on and remove them. Next remove the three clips that hold the rubber air duct onto the side of the protector, and remove the protector. Once the protector is off, you will need to remove the grill from it. To do this turn the protector upside down, you will notice that the grill is held on with small metal clips. To remove these clips slip a small screwdriver between one of the raised parts of the clip and gently pry it a bit, next do the other side and remove the clip.

Now reinstall the intercooler protector, don't push back the clips for the rubber duct yet. Now test fit your fan to see if it will fit inside the intercooler protector and sit flush on the intercooler itself. If it does, the next step is to gently lower the hood, to see if it will close, don't drop the hood down, File Shroudbecause if the fan is to tall you will have a nice dent in your hood scoop. If the hood seems to push right down, the next thing is to get something that is about 1/16 of an inch thick, and see if you can fit this between the highest point on the fan, and the underneath of the hood scoop. If you can, then you are ready to go to the next step of securing the fan to the protector, if not you will have to file down some of the shroud to lower the fan. The best way to file the bottom of the shroud correctly is to keep checking if it fits flat on a piece of glass after filing. Of course now that you have filed the shroud down a bit, there's a good chance the fan blades will now be too far down, if this is the case you will have to remove the blades section Sand Bladeand find a way to raise it up, I carefully sanded the stem for the blade section, of course this is all dependent on the design of the fan you get. When filing the blade section it is important that you be very careful to sand flat, otherwise the blades may wobble. Once everything is fitting correctly, and the hood can close with the necessary clearance between the fan and hood scoop, you will need to secure the fan to the protector.

To secure the fan I made four Click For larger Viewbrackets (click on the image to view a larger one), each with a hole to fit over four of the pins that used to hold on the grill, and a hole to attach them to the fan. I wasn't sure that the four clips could hold the fan, but they did, and the whole setup is fairly sturdy, and once protector/fan setup is in position on the intercooler it won't be able to move.

Note: After the mod is complete, you will need to check that the rubber piece on the bottom of the hood scoop is still seating flush on all the sides of the protector, if not some trimming of this rubber piece may be needed. It is important that this seats fairly good, otherwise the fan will also be sucking in hot engine bay air.

I wired my fan so that whenever I turn the ignition on the fan comes on. I placed the connector for the fan in a location that was easy to get at, in case I ever want to disconnect it. If the fan you buy does not come with a connector, I suggest you buy one, and make sure the connector is of adequate size to handle around 30 amps. You will also need to purchase a 30 amp relay, I used a Bosch relay, and a connector for it. If you can't get a connector for the relay, you can always buy four female spade connectors of the correct size, and make your own connections. Remember to get the right gauge wire, 14 AWG gauge would be best for the high amp connections, and 18 AWG gauge should be good for the lower amp connections.
120 Amp Fuse
First I connected up the relay. Start by disconnecting the negative terminal of the battery, then remove the two 10mm nuts holding the fuse box on to the battery holder. Then remove the two brackets from the fuse box, this will give you more room. Remove the fuse box cover, and then lift the fuse box, the wires will have it tight to move, so that the bottom is visible, now remove the bottom of the fuse box, there are some clips holding it on, these might give you a little troubleFan Relay Diagram, I can't remember exactly how they work, but it's not hard to figure out. One of my clips broke, it was brittle from all the heat, so don't get too worried if this happens. I used the the big 100 amp fuse, which is held in it's connector by two bolts, to source power for the fan. Crimp some of the thicker 14 gauge wire to the correct size ring terminal (I like to solder the connection as well), and bolt the ring terminal to the 100 amp fuse. Run this wire to one side of the 30 amp fuse holder, and from the other end of the fuse holder, run a wire to Terminal #30 on the relay. Now you will need to find a 12 volt ignition source to power the relay. I will leave this up to you as the source I used, can only be used if you have your radiator fan is running all the time. Run a wire from the 12 volt source you have found to Terminal #85 on the relay. Next you will need to ground the relay. To do this run some of the thinner 18 gauge wire from Terminal #86 to a ground. Fan Wires DiagramNow run some of the thicker 14 gauge wire from terminal #87 to the positive side of the fan connector. Make sure you hook up the fan wires the correct way, otherwise the blades will spin in the wrong direction causing the fan to pull air form the bottom of the intercooler, instead of pushing air through it, which wouldn't be very good. Now place a 30 amp fuse in the fuse holder, put the fuse box back together, put the brackets back on the fuse box, and attach it back to the battery holder, and put the negative cable back on the negative terminal of the battery. Now you are ready to test if the fan works when the ignition is switched on. Switch on the ignition and watch your new intercooler fan at work. A simple test to see if the fan is spinning the right direction is to place your hand under the intercooler and feel if any air is coming through.

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This page was created by Dennis Heath.
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Please note that I am not a mechanic by trade, and that any information offered on this web page is free and without guarantee. Should you choose to perform any of the procedures listed on this site, you will be doing so of your own free will, and I will not be held responsible or liable for any damages that might occur from using information obtained here.