Turbo coolant return line replacement

[psychobabble]

I searched across several different forums and found limited but not entirely useful information about this. The coolant return line from the turbocharger on my kid's 2011 A4 2.0T separated at the metal compression union between the metal line and the hose. I purchased a new hose/line, as shown in this photo. From under the car, I can see the banjo bolt, but I've read mixed opinions about being able to remove and replace this without removing the turbo. I found a video where someone cut the metal line and spliced a new hose onto it, but I can't believe that would be a permanent fix. Has anyone been able to do this without removing the turbo, and if so, how? Does anyone know of a write-up or anyone who can offer some guidance?

[Zuzuwu]

You can remove it it’s just really hard. I had to remove the rad support on my car to get access to the bolt on the turbo side that faces the engine. I tried every tool i could find and nothing would get in there. Once you have the rad support out it’s a 5 minute job to replace the line


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[psychobabble]

Thanks for the reply! Do you mean putting the front end in service position? Or removing the entire radiator support assembly completely?

[BradyBoi55]

I searched across several different forums and found limited but not entirely useful information about this. The coolant return line from the turbocharger on my kid's 2011 A4 2.0T separated at the metal compression union between the metal line and the hose. I purchased a new hose/line, as shown in this photo. From under the car, I can see the banjo bolt, but I've read mixed opinions about being able to remove and replace this without removing the turbo. I found a video where someone cut the metal line and spliced a new hose onto it, but I can't believe that would be a permanent fix. Has anyone been able to do this without removing the turbo, and if so, how? Does anyone know of a write-up or anyone who can offer some guidance?

when I was rebuilding my motor I forgot to put a washer on that line and I had to pull everything back apart to tighten it. I drained the coolant put the car in service position and backed out the nuts on the studs attached to the cylinder head holding on the exhaust manifold/turbo. I didn't take them completely off, just enough space to fit a low profile ratchet. I then removed the line, installed the washer and reinstalled it. It took me about 2 hours. Replacing the line wasnt hard, it was getting to the line which was the challenging part. I wish you the best of luck with the four interlocking rings of doom!

[psychobabble]

Thanks for the advice. Why is it that we must go through hours of work just to get to something that takes a few minutes to fix?!

[psychobabble]

Thought I'd update the thread in case anyone else has to replace this coolant line.

First off, the banjo bolt does not have a 12 point triple square head like the coolant inlet line. It is a hex head. Not sure why it is different from the others.

Although I put the front end in service position, it turned out I completed the job without needing to do so. I was not able to get to the banjo bolt from the front of the car. Too many obstructions and no room. I ended up removing the airbox, which helped a lot. I also removed a shielded plastic line (PCV maybe?) and secured it to the top of the engine with a bungee cord. That gave me just enough clearance to get a stubby 8mm hex key on the bolt. I had my daughter hold it in place and I used a ratchet extension and a small hammer to break it loose. It was too baked on to break loose by hand. I installed the new line using a stubby 8mm socket. Securing the bracket helped to hold the line in place while I used standard pliers to turn the socket (no room to get the ratchet in there). I put duct tape on the socket body to get a better grip. My only concern is that there was no way to get a torque wrench on it. I just tightened it to the point where I felt I wouldn't over-crush the crush washers but enough to ensure no leaking. Fortunately none thus far.

Knowing what I know now, I could probably do the job in less than an hour, not that I ever want to do it again! Hope this helps anyone else needing to do this.

[Smac770]

Factory probably used the wrong banjo bolts, like on mine. They had the triple square bolt on the coolant supply and the hex head bolt on the oil supply, which is backwards. I had to cut down a triple square bit to get the coolant supply banjo bolt out because of the frame rail.

The oil supply banjo bolt is https://parts.audiusa.com/p/48737210/WHT000223.html
The coolant lines banjo bolts are https://parts.audiusa.com/p/48000387/06A145541J.html