Has anyone replaced sunroof drain hose ?
 

My front right drain hose from the sunroof has bad leak in it.
Read the manual says slide new one up from the bottom but does not look that easy.
Also there seems to be two joiners in the a pillar. Probably joiner broken.
Thinking of getting the same size rubber tube instead of oem.
Any body done this??
How hard is it to do ?

Look up fish wire or how to fish cable. Electricians do this type of work daily - that is to thread cable through conduit piping.

The path sounds to be unobstructed. What you could do is put down a "fish" wire first, or even hook onto the existing pipe, then pull in the direction you need to go, voila the new hose shows up at the destination if all things go to plan.

I did this for my boat routing fuel lines, steering cables etc.

These are just ideas, as I have not threaded sunroof pipe on the A8 (except a short pce on the Beetle)

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I am sure if they really tried they could make the drain hole smaller


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Well front left drain hose was a bust.
Hoes broke in the middle ,I think it was already broken.
Ends of the hoses have ridiculous small ends.

Last photo is drain hose is behind the washer bottle that would take all day to get out.
With half the hose still stuck in the lower A pillar and immovable I siliconed up the drain hole in the sunroof.
The amount of water that can get out through the end plug is very small just a trickle.
Any dirt or crap that goes down the hose stays in the end and blocks the outlet.
I might open the other side up a bit.

I have never understood the need for the ends of the hose to be shaped like a slit, I'm guessing it's too work like a one way valve but let's be realistic here if the water level was the height of the sunroof I think you would have bigger concerns.

Perhaps it's to prevent air pressure differences making a noise in the sunroof when your driving, who knows? Perhaps you could push a little piece of drinking straw in there to hold the slit open making it easier to drain.

Just a heads up the drain hoses are held in place on the pillars with expanding foam so you can't just pull out the whole thing.

The VW Beetle has the same rubber gaiter valves. Totally jammed with sludge too. I kinda wondering what in the heck they would need that for.

High pressure air is under the car, so I suppose that could feed or possibly pressurize the sunroof cavity causing a thumping effect? (Pressurize, lift, blow off, drop.)

I tried the weed wacker line down my drains yesterday. The line is garbage I just got about 4 ft in. My sunroof is very clean, because the PO had parked the car inside 100%.

Sealing off the one side is a good workaround solution to R/R the pillars etc. I guess you have to remember to park the car leaning to the side that is open, or the water could pool on the sub-roof.

Yes I read somewhere that it had foam fill in the a pillar
In the service manual it says slide hose out from the Bottom and slide new one in.
Mine is in there solid.
I will have to check to make sure I have not blown off any of the end caps.
Should be easy to check I think the water would end up on the floor on the front ones.
Just had a massive 2 days. Pulled the roof lining as the foam backing was stuffed.
Got it redone with a non foam backed lining.
That was a nightmare getting it out and back in.
Swapped out the sunroof. Had broken tracks for the roof slider. Had a spare I bought about a year ago. Stuffed around with drain hoses for too long but had to done.
Spent. Most of the morning trying to get the sunroof sliding correctly.
Best way I finally found was to manually wind it closed and popped up.
Undo the roof motor and run it with the switch back and forwards a couple of times and set switch to closed and popped up then bolts the motor back in . Sweet.
Just got to clean up the aftermath after a spell.

Can you blow air down the tube to try and clean and obstructions?

You could but risk blowing the ends off and you will never get the back on. And then I think it would leak on the floor.
Just to get at right front rhd take wheel off remove wheel arc lining then it's behind the washer bottle which I can see no easy way to remove. Just moved enough so I could just reach the end plug to the photo.
In hind sight I would probably use a small funnel with tube small enough to fit down the drain a few hundred mm and pour half a litre of water in slowly and see if it drains out in the wheel well.

RE: Using air. You DON'T got at it with 100PSI. Turn the regulator down to something mundane like 5-10psi really low anyway. You use a combination of poking with a wire and the air. The air signals the line is clear, because you can hear it hissing out the other end.

This is how I have done my drains for years. Having said that I am pretty sure our buggy has one blocked front drain, the other 3 are good.

I think you guys have an image in your mind of full shop pressure blowing the lines to smithereens - which it will!