Avdwaal1

2006 Audi A8. I am about to replace the thermostat,waterpump and timimg belt (kit). I have taken the bumper cover off, bumper, AC "screen" and unbolted the radiator. How exactly does one get the coolant hose off? the manual just states "remove coolant hose", it doesn't say how or where to take it off. I have tried pulling on the hose and then some coolant drips out but I don't wanna break anything. Is the hose suppose to come off from the radiator itself (metal) or do I need to somehow get it off from the connecting pieces? DO I need to turn it or remove a clamp?

I have search the www & forum and came across some posts about this but none actually said how to do it.

tnx!

MP4.2+6.0

There is a securing clip built into the hard plastic housing where the hose pushes onto the radiator. It is meant to be a quick connect type set up. Fortunately Audi typically designs it so you extract the clip in an accessible area. Look very carefully for the butt end of the clip--it is shaped kind of like a squashed "C"--where you should see some stainless steel about the thickness of a 2" paperclip. The plastic on the butt end and the opposite end are molded a hit thicker with some protrusions than the plastic is near the waist/middle of the clip on both sides of it. If you are on the opposite end, you will see two wire ends, like the end of paperclip wire. You need to pull that clip back from the butt end about ½-¾" Typically you can pry it out, first with a fine flat screwdriver, then with a long handled one or sometimes some needle nose pliers, to get it pulled back. Once you do so, the hose pulls straight off. Inside of that plastic end where the clip goes, you will find a large o ring, which you should typically replace. All the more so if you found pulling on it, some water came out. To put it on, clip can be in its final locked position, and you just push it on until the clip settles home again.

mishar

This may help:

Avdwaal1

Thank you, I got the radiator and the fans off!
While I am in there should I replace the accessory belt and its belt tensioner? What else is recommended?

mishar

Replace the belt. Check the tensioner and if bearing is making noise replace it too. Not cheap though.

MP4.2+6.0

+1; as I think Mister Bally can confirm, use an OE/OES serp. belt and don't cheap out.

Mister Bally

Read this thread and look at photos linked in two of my posts:

https://www.audiworld.com/forums/a8-...-note-2808704/

Avdwaal1

I have replaced the thermostat, waterpump and timing belt, car is running good but it leaks coolant at the lower radiator hose quick connect coupler. thanks all for your help.

Does anyone has a part number or know where I can buy the O-ring that is in the coupler?

Arthur

mishar

It's not shown as a spare part, but you may ask nice guys from audiusaparts.com. If you find size or have old o-ring, you can buy it at any auto part shop.

MP4.2+6.0

if it is a pretty large diameter (call it maybe 1 ¼" more or less), they sell that as a piece part and it fits both lower and upper main hose quick connects on the W12. There is a smaller hose on at least the W12 right near the lower hose (drivers side). The O ring for that one (maybe about ¾" from memory) is not sold separate from the hose. That one was the dripper on mine. Not sure how this translates to 4.2 hose sizing though. Romney at audiusaparts knew what I was after when I checked with him. As Misha said, H/W store o rings are another choice, if you have hose and/or o ring in hand to match. I think the Audi EKTA parts diagrams may also have the specs (diameter and rubber thickness) with the part numbers.