Trying to fix a coolant leak

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Protg5
Howdy y'all,
I've got a coolant leak coming from behind the thermostat on my '03 P5.

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You can see it dripping from where the tube goes into the thermostat housing. Is this the bypass tube?

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Here's a diagram view of the area. I can see the tube on every diagram I can find but none of them are labeled.
My guess is it's an o-ring that needs replacing between the tube and the housing? Can anyone point me in the right direction?
I few months ago I started finding a small puddle under the area once or twice a month, but as the weather has cooled down it's been an almost daily occurrence, especially on particularly cool nights. Now I think it's beginning to just slow drip regularly, so I can't put it off any longer :'(
 
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Here's my take on it.
If it was my car, I'd maybe try some stop leak or oatmeal or pepper but my car's worth ~ $400.
That stuff can clog up your rad and other stuff.

The problem is that you can't just disconnect the one pipe. They are rigid and you would have to disconnect both and the thermostat housing from the engine.

You may find an o-ring to replace or if not and if it were me, I'd try some pipe thread sealant.

It's waterproof, gas, oil and acid-proof and stays soft for the long-term.

 
That's a good idea, I'm all for the easy fix. I only need it to last me another month or two. I'd never heard of using oatmeal or pepper, that's incredible.
I have no idea how much of an ordeal it is to get to the o-ring or whatever is in there, I don't want to have to disassemble the whole thermostat assembly without knowing that I'll be able to even get the tube out. I'll probably clean the area off and cover it in sealant, from what I can tell it's more of a drip than a high-pressure leak so I bet that'll work great.
 
I've never tried pepper or oatmeal, but I'm sure I would if I was camping and didn't mind sacrificing some spice and breakfast to get home. Lol

If it were me I'd try something like this.

 
I went and took a look at my parts car and it looks like that pipe can be removed separately.

You'd need to remove the rubber rad hose at the one end and the bracket bolt in the middle.

I don't know how hard it would be to access everything.



 
I went and took a look at my parts car and it looks like that pipe can be removed separately.

You'd need to remove the rubber rad hose at the one end and the bracket bolt in the middle.

I don't know how hard it would be to access everything.




wow that's nasty LOL
 
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