MackayWRX.com

Water Spray Set Up, with genuine subaru dash switches

(Taken from Rexnet:)

-Takes about 4 hours to install.
-Test everything before it is properly installed. I cannot stress this enough.
-Practice whatever it is you are about to install on something that is not associated with the end product e.g. If you are going to install a washer motor, first practice drilling a hole on another bottle that is going to be thrown out. Otherwise you could be up for some $$$$.
-Buy everything in one go. I had to go back to the same shop 10+ times.
-Learn to solder very, very well.
-Ask questions from experts in the field if unsure.
-Print out the wiring diagram and get a mental picture of where everything needs to go.
-Make sure that wires are the correct length.

Wiring diagram:

Shopping List:

Most, if not all, can be purchased from an auto parts store or electronics store.
– Soldering Iron
– Relay (12 volt, 30 amp with inbuilt fuse holder)
– Fuse holder
– A packet of fuses
– Electrical Wire
– 6.4mm male and female spade/tab connectors
– Vampire clips
- 2.8mm mini female spade lugs WITHOUT and plastic on them. These are used to improvise a harness for the dash switches. If they have plastic on the end they sit at a spastic angle when put in the dash switches (Dick smith part number H5036)
- A washer bottle kit (includes motor with wiring, rubber grommet, washer chord, t-piece, bracket and washer bottle). I got one from Super Cheap Auto.
– T-piece for vacuum line
– Heat shrink wrap
– Ring connectors (10.5mm)

Stuff to get of nrg/mrt website.
– Genuine auto and manual STi water spray switches
– Hobbs switch (I think mrt can supply Hobbs switches if you ring them)
– Genuine Subaru water spray nozzles x 2

Other stuff/tools needed:

– Socket set
– Torch
– Long nose pliers
– Wire cutters
– Swiss army knife (came in handy!!!)
- Some sort of testing apparatus to test if wires conduct properly. I did this because a guy once told me that sometimes solder actually acts as an insulator or something if it is not melted properly by the soldering iron. So I got paranoid. Refer to the testing comment. I used a little motor and a 6v battery.

Washer bottle kit…

First step: Nozzles

I got a 10mm drill bit and drilled holes in the shroud. I managed to push them through after a bit of persuading and kind of making the holes 11mm by rotating the drill bit. Dodgy I know, but hey this is DIY and it worked. However it chewed the nozzles a bit when I "persuaded" them through, but the top of them look fine so I'm happy with it. I then used the t-piece and washer line from the washer bottle kit and hooked up the washer line to the nozzles. Refer to pics to see how I did it.

Second step: Washer bottle

Test drill bits until you find the correct one that fits exactly in the hole of the washer bottle that comes in the Super Cheap kit. Practice drilling holes in this crappy super cheap washer bottle. I found that if it is not done slow and steady then when it comes to the real thing it will create divots that will need either fibreglass to fix or replacement of the good washer bottle. I also started by drilling a hole with a smaller drill bit (about 5mm) to act as a guide for the larger one. Be careful and practice!!!

Once you have got the hang of drilling holes in the supercheap kit washer bottle remove the washer bottle from the car. The clips that supply power to the pumps are a pain to get off. Also when you disconnect the hoses for the pumps water will leak out everywhere. Pour out water and drill a hole in the same position I have. Bits of melted plastic may need to be removed with a Stanley knife to put the rubber grommet on. After the grommet has been put through the hole, screw the pump in a little bit. The pump that I used had a filter that also doubled as a nut to help hold the pump in the bottle. I held the nut with a long spanner and screwed the pump on the rest of the way. It fitted really tightly and so far, fingers crossed, it has not leaked.

Before putting washer bottle back on make sure the pump is actually pumping water by hooking it up to a 6v battery. It needs to be primed or something. I didn't do this and had to take everything back off. Pain in the ass I tell you!!! Also if you are doing this in one day and don't need the car, you might want to leave putting the bottle back on properly until after putting the wiring for the relay in place.

I then attached the washer line from the nozzles to the pump and by using a little 6v battery tested to make sure that the nozzles sprayed. Not much water came through, but it was off 6v so it was expected.

Third step: Wiring the switches

Apparently the harnesses that Subaru make for water spray switches are priced just past $1000. The same thing can be done DIY for about $5. Using the wiring diagram, place the gold spade connectors in their correct positions.

Note: make sure the spades fit onto the tabs on the back of the switches before you do any soldering. Some had holes that were too small and did not fit so I put them to one side to be discarded.

Take each spade off the switches one by one and solder wires on the spade connectors. All the electrical wires should be about 30cm to start with except the ones that end up going to the "86" on the relay. Make these ones a couple of metres to be safe. It is probably better to have too much wire connected than not enough. You might also want to colour code or label each wire so you know where it goes and what it does. After soldering and clamping the spade, test that each wire conducts by using the testing apparatus. When done testing use heat shrink wrap to insulate the spades (refer to diagram). I used a lighter to apply heat. Trimming with a pair of scissors may be required as sometimes the heat shrink goes over the front of the spade. Reconnect each spade after the heat shrink step to its correct tab.

Fourth step: Installing the Hobbs switch

To install the Hobbs switch I cut the mounting bracket that came with the supercheap washer kit. I then bent it into an "L" shape. I undid one of the bolts from the intercooler mounting bracket, I used this to hold the Hobbs switch in place. After undoing the bolt, use it to make sure that the hole drilled in the bracket is big enough for the bolt to fit through. Drill two holes, one for the Hobbs switch to pass through and one for the intercoller bolt to pass through. Then it is just a matter of doing the bolt back up and it sits nicely. Be careful when undoing the intercooler bolt as they can be painful to get off so use a socket set!!!

If you buy a Hobbs switch from the NRG website you probably won't have to do the whole improvised bracket thing as it already somes with a bracket thingy. Trust me it is best to get one off that website, I had so many dramas buying a Hobbs switch locally, but that is another story…

Fifth step: Relay.

If not done already, put the washer bottle back in without doing up the screws (connect up the motors etc). This will help you if you want a neat install because some of the wires can be hidden under the washer bottle.

On the relay there are some numbers (30, 85, 86 and 87) on the bottom that can be also be seen on the wiring diagram. I bought one with an inbuilt fuse holder and put a 15 amp fuse in it. I attached the relay next to the fuse box. I had to drill the hole out a little.

Wiring the relay:

Make sure the cables are the right length before soldering!!!

30: Solder a ring terminal on this the end of this one.

85: I connected 85 to the negative wire on the washer pump. I then made an "extension chord" by using male and female spade connectors as it needs to be earthed at the front of the car. You will need to solder on a ring terminal at the another end.

87: I joined this one to the positive power on the washer pump.

86: This one needs to be made longer by connecting another piece of wire onto it. On the end solder on a spade connector.

Connecting the relay:

30: I undid one of the nuts on the positive terminal on the battery. I put the ring terminal on the bolt and did the nut back up.

85: I undid and attached to the bolt used to earth the battery at the front of the car next to what I think is the coolant overflow or something.

87: joined already so no need to do anything.

86: On the Hobbs switch it has writing on it: NC (Normally closed) NO (Normally open) and C (Closed). I connected it to C (Closed) using the spade connector.

Sixth step: The switches…

This will be fun trying to describe…

I took all the spade connectors out of the back of the harness.

I then took the dash off. There are two blank spots for the switches to go into (one has a harness attached to the back). Push the blanks out and push the new switces in.

Before the tabs go back in some of them need to be joined together i.e. the purple illumination, orange illumination and the ignition on ones.

Using the orange illumination as an example:

Cut the wire from the auto switch so its about 10 cm in length. Cut the one from the manual switch so its about 5cm in length. strip and solder the two wires about half way down the auto switch wire. It will look like a y-shape when finished. Check that they work and then heat shrink wrap where they are connected.

Do the same for purple.

ignition.. do the 5cm thing, but the 10cm one make it 15cm instead (if that makes sense). Connect to the fuse holder. The fuse holder obviously has two wires coming off it. On the other wire solder on some wire that is easier to work with, then heat shrink wrap.

Now wiring them so they work………….

First of all ground. Look to the right of where the fuses are in the car. To the right of that there is two bolts sticking up. Cut the wire so it is the correct length then attach a ring terminal on the end. The bolts have a little thread on them so I put the ring terminal on and got a nut and screwed it on to hold it in place. It is now earthed.

I attached the wire for manual spray to the back of the switch for this next bit. I did this by leaving the door open and bonnet up and loosly conneting it via the outside of the car to the NC on the Hobbs switch.

Power… Hmm maybe a bit dodgy how I did this. I turned the ignition on. I then stripped the end of the wire. There is a pretty big harness above where the fuses are in the car. I poked the bare cable into where the wires meet the harness and pressed the manual button until I heard the motor going and water spraying. I then turned the ignition off and checked that it didn't work with the ignition off. I then cut the cable from the switches to the desired length and used a vampire clip to piggyback off the wire in the harness. I undid a nut that was under the dash and I used this to hold the fuse holder in place.

Purple/Green illumination.
The lights of the car have to be on to do this, so you may need a dark garage and a torch. There was a spare harness behind one of the blank switches, but you could also unplug the harness from the back of an existing switch. I stripped the end of the wire from the waterspray switch and poked around until I found the correct wire to piggyback off. I then used a vampire clip to piggyback off the wire.

Positive power out…

Lift up the carpet on the passenger side.

Firstly I ran these wires under the dash and behind the ash tray (I used a coat hanger to get the wires through). Under the carpet there is a place to go through the firewall, once you lift up the carpet you should see a rubber seal. I taped the ends of the wires together and poked a coathanger in between. I then poked the coathanger throught the rubber seal in the firewall. Then I got yet another coathanger and fished for the wires and jiggled until the original coat hanger came off. Once I got the wires it is a matter of pulling the coathanger back out of the rubber seal and pulling the wires up. I then had to reach down and pop the seal back in. Helps if you have skinny arms and patience.

I then needed to attach both wires to the Hobbs switch. I cut the wires to the desired length and soldered spade connectors on the end. I did the soldering by putting a cardboard box over the engine bay. I then heat shrink wrapped where I soldered. I connected the manual wire to NC and the auto wire to NO.

Seventh step: Connecting the Hobbs switch.

I cut the boost line that connects to the manifold next to the BOV line. I put the t-piece in, then connected the t-piece to the Hobbs switch using some vacuum line (the blue stuff in one of the pics near the start).

Off a 12v battery this setup sprays a lot of water!!!