KwikStix

What's up guys!

I finally got around to installing my Merc Racing heat exchanger this weekend. The install was pretty straight forward, but was time consuming (mainly because I was recording every step of the process). Thanks to everyone that answered any of my previous threads asking for information on installing I've of these and asking about the coolant system. Also want to give a big thanks to Jose at Merc Racing for his excellent customer service throughout this process. OK, on to the diy.

Difficulty Level: I'd say this was a 2/5 difficulty if you know your way around the car decently and know your tools. If not, then it's probably a 3/5. Just make sure you have the right tools.

Tools List:

-T25/T27/T30 Torx Bits/drivers/etc.

-M8 Triple Square

-Phillips Screwdriver

-Power Drill

-5/16 metal drill bit

-10mm socket

-13mm socket x2 for crash bar removal/assembly

-1/2" socket x2, one of which being a deep well (or substitute a 1/2" open ended wrench)

-Rubber Mallet

-Channelocks

-Cline/pliers of some kind

-Hose cutter

-Something that can cut through metal in case you have to trim your bracket/bracket bolts

-Coolant Fill Tool/Air compressor (way easier than bleeding the system)

-Protective Glasses for when you dremel... trust me, just wear them.

-Protective Eyewear

-Protective gloves (think mechanix style)

-Latex gloves (we are working with coolant)

-Siphon

-Good work light

-Drain Pans/buckets

-Shop Towels/Rags

-Small section of 2x4

-Shop-Vac

-A friend you bribed to help you do this

-Beer

-Music

Materials List:

-Merc Racing Heat Exchanger

-Merc Racing Installation Kit. Alternatively you can piece this together yourself at lowes/home depot and save yourself some coin. I will work on exact sizes, but the basic run down of parts you need are:

-6' heater hose (this gives you extra to pay around with)

-6 hose clamps

-2 hose couplers/connectors (to mate the new hose to your oem coolant hoses)

-4 long bolts/washers/locking nuts to go through your crash bar and attach your mounting brackets.

-1 gallon OEM Audi Coolant Concentrate

-1 gallon DISTILLED water

Noteworthy Information:

-Merc Racing just announced the release of a new design to their Heat Exchanger for the 3.0T. It can come with a bleed screw on the heat exchanger art the buyers request. They also updated the brackets so the exchanger doesn't sit so close to the condenser in certain cars. It's not a problem on the A6 3.0T, but I've read it's a right fit on the A7 and S-lines models.

-Please, for the love of all things Holy, give your car ample time to cool down before attempting this project. Hot Chemicals burning your flesh are no bueno. I let my car cool overnight and started in the morning.

-The video starts off with the car lifted and the front bumper removed. If you need help removing the front bumper, please reference my DIY on that here: https://bit.ly/2HStZIK

-If you are able, lift both the front and rear of the car to get it as level as possible if you plan in doing a coolant flush (I used ramps for the rear, but my car isn't lowered). If not, you only need to lift the front.

-I highly suggest using a note pass and pen to write down what what type/size/amount of books you remove during the install, as well as the location you took them from. This will help a lot when you put the car back together.

-If you are just swapping out the HX, and not changing your coolant, you can use vise grips to close your oem coolant hoses and minimize lost coolant. It is a good idea to pre-fill your Heat Exchanger before attaching the hoses to minimize the amount of air that gets into the system.

-I highly suggest bribing someone with beer or food or both to help you out. They are really helpful when it comes time to marking your bracket location on the crash bar, but you can use a floor jack to support the HX if you are by yourself.

-Wear protective gloves and Eyewear anytime you are dealing with fluids or drilling/cutting metal.

I will update this thread if I remember anything else in the section below. Please comment if you have any suggestions or helpful hints for others.

Updates:

Update #1: In the video, when mounting the brackets to the crash bar, I accidentally put the washers on the bracket side instead of with the head of the bolt. This was a slip of the mind, and I didn't think twice about it, because two of my bolts sank right into the groove that runs on the front of the crash bar. This locked them in and I didn't even think about putting a washer between the two. Keep this in mind when you install.

Update #2: @ 5:50 I started explaining how to remove the passengers side coolant hose from your stock heat exchanger. It goes without saying, but I didn't mention that you do the same thing to remove the drivers side coolant hose as well.

A couple minutes later I go over the contents of the merc racing install kit and mentioned that I only used 4 of the 6 hose clamps. That was a lie. I used all 6.

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And on to the video! Make sure you watch it with the sound on as there is a voiceover by yours truly talking about each step of the process.

Please subscribe to my youtube channel. It's still new, and thus is only the 2nd video on it, but I'm hoping to continue adding C7 specific videos as I can.

You can also follow my C7 Instagram page @AudiC7Owners

KwikStix

Update #1: In the video, when mounting the brackets to the crash bar, I accidentally put the washers on the bracket side instead of with the head of the bolt. This was a slip of the mind, and I didn't think twice about it, because two of my bolts sank right into the groove that runs on the front of the crash bar. This locked them in and I didn't even think about putting a washer between the two. Keep this in mind when you install.

KwikStix

Update #2: @ 5:50 I started explaining how to remove the passengers side coolant hose from your stock heat exchanger. It goes without saying, but I didn't mention that you do the same thing to remove the drivers side coolant hose as well.

A couple minutes later I go over the contents of the merc racing install kit and mentioned that I only used 4 of the 6 hose clamps. That was a lie. I used all 6.

culi

Nice video. I just bought a vacuum coolant refill tool because of what I saw in this video. Now I have to buy an air compressor.

KwikStix

check your local pawn shops for some good deals

wes8398

I'd just like to say thank you for this. All this time later, and plenty of folks are still using this tutorial. It's much appreciated.

KwikStix

My pleasure man. This forum isn't as active as the C7 sub forum on Audizine so I keep most of my updates over there... but either way if you subscribe to the youtube channel you will see everything I post.

I'm glad this helped you out.