Brown residue on walls of coolant tank.

[clelland1982]

I've recently bought a 1999 Golf 1.4s from an auction. I've noticed there is a brown residue a little like moist brown sugar around the inside walls and lid area of the coolant tank.

The coolant itself seems quite clear though. There is no white residue in the oil that i can see and i don't seem to be losing any oil or water.

Any ideas what this could be and what i could do about it?

Edited by clelland1982 on Wednesday 16th July 00:18

[phumy]

It could just be crud, sediment or residue that had formed inside the radiator over many years. Get your finger in the expansion bottle (when cold) and check out if it feels or smells (the brown stuff ) oily, obviously if it does then it might have other issues.


It might pay you to give the cooling system a bit of a flush after warming it up first, dont get it too hot as its mighty dangerous when disconnecting pipes when under pressure. Drain the coolant, flush it through with a hose then refill with the correct mixture of water/antifreeze. A trick with the expansion bottle, when the wife is out or not looking, put it in the dishwasher on a hot wash, it will come out like new, (i have the black eye to prove it).

[brisel]

phumy said:

(i have the black eye to prove it).

The sign of a true petrolhead!

[cupra20vt]

ive read before that if a non VAG coolant is used it can turn the pink coolant brown, maybe residue from this?

[Dr G]

cupra20vt said:

ive read before that if a non VAG coolant is used it can turn the pink coolant brown, maybe residue from this?

Certain I've heard this mentioned before - wouldn't surprise me if someone had tried to maintain it on the cheap.

Coolant flush and a full service to VAG spec certainly wouldn't hurt.