black stuff in radiator
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2nd Gear
Joined: Jun 2012
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black stuff in radiator
I read a thread about black substance in radiator of C4 (I think). My C4 has it too, but I know what caused it. The upper radiator hose, which I believe was the original hose failed. The rubber broke down, deteriorated and released the black tarry substance from the rubber compound into the radiator. I havent been able to get it all out as yet, but it seems to pose no threat to the cooling system. It is just in the upper part of the radiator and seems to want to cling to the nylon radiator shell. I plan to syphon it off as it appears. Will let you know if it works.
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Welcome to the forum. Moving this thread to C4 Tech for any updates.
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I've never heard of it either, but if indeed it is broken down rubber hose material, I think that I would drop the knock sensors and flush the entire coolant system and then start replacing hoses.
There should be nothing in the coolant system except for coolant.
There should be nothing in the coolant system except for coolant.
