Audi TT
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Discussion

RZ1

Original Poster:

4,507 posts

236 months

Monday 2nd December 2013
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Chaps hoping for some help. My TT water header tank seems to have a frothy/foamy type of layer above the water.
The water level is perfect, no mayo type sludge on the oil cap, it has coolant, but not sure what type, however its pink.
Also along the top of the header tank is a brown muddy type of stuff, hard to explain so will take a pic when I get home this eve.

Seems to be like this all the time, after a run and also after its been standing for a few days.

Any idea what it could be

HustleRussell

26,581 posts

190 months

Monday 2nd December 2013
quotequote all
If there are no other symptoms I'd suggest that a cooling system flush/refill ought to clear it up. This comes with the added bonus that you'll be sure that you have the correct antifreeze of the correct concentration in the car for the winter.

That said, brown sludge tends to be an emulsion of oil and coolant. Hopefully you don't have any cross contamination occurring in the engine.

RZ1

Original Poster:

4,507 posts

236 months

Monday 2nd December 2013
quotequote all
HustleRussell said:
If there are no other symptoms I'd suggest that a cooling system flush/refill ought to clear it up. This comes with the added bonus that you'll be sure that you have the correct antifreeze of the correct concentration in the car for the winter.

That said, brown sludge tends to be an emulsion of oil and coolant. Hopefully you don't have any cross contamination occurring in the engine.
The engine temp seems to run cool, but otherwise its ok.
Have done a couple of 3 hour plus journeys and never over heated.

I do know that you have to use a certain audi coolant with some cars, so not sure if this is due to someone mixing the wrong type of coolant.

HustleRussell

26,581 posts

190 months

Monday 2nd December 2013
quotequote all
Sounds like an opportunity to change that broken thermostat as well then!

Hopefully the brown stuff is just rusty deposits.

If you have any doubt about which coolant to use, either get it from a dealership (it'll probably be reasonably priced), consult the book or ask on an owners forum.

V8RX7

28,982 posts

293 months

Monday 2nd December 2013
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How long have you owned it - sounds like it could have Radweld or similar in it.

RZ1

Original Poster:

4,507 posts

236 months

Tuesday 3rd December 2013
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V8RX7 said:
How long have you owned it - sounds like it could have Radweld or similar in it.
Not long about 2 months

bakerstreet

5,050 posts

195 months

Tuesday 3rd December 2013
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RZ1 said:
The engine temp seems to run cool, but otherwise its ok.
Have done a couple of 3 hour plus journeys and never over heated.

I do know that you have to use a certain audi coolant with some cars, so not sure if this is due to someone mixing the wrong type of coolant.
Long motorway journies aren't the best to test overheating as you have air being forced into the rad and the engine will run a bit cooler anyway. If its running cold, then I would look at the thermostat and get the coolant changed at the same time.

I would make it a priority, as you don't want your engine running at 25C in the middle of winter.