The question is what is the oil tank made of on a 1981 911SC?
During annual service a Porsche specialist stated "Oil tank is corroded and rusting on the inside." He seemed to be hankering after changing the oil tank. I said that I thought that the oil tank was made of stainless steel but he said no, it is an internally copper coated tank. The visible part under the wheel arch certainly is very clean and non corroded. It has the appearance of stainless steel. I have now checked the tank and believe it to be made of stainless steel albeit with a brass filler neck and maybe other connections. The so called rust was a dark sticky deposit around the top inside of the filler neck. The deposit was confined to the top 50mm or so. A few particles were present in the deposit that I could not identify but I doubt that they were rust. I checked the tank internals with a powerful torch and from what i could see it was very clean.
All help and comments will be appreciated. Thanks in advance.
During annual service a Porsche specialist stated "Oil tank is corroded and rusting on the inside." He seemed to be hankering after changing the oil tank. I said that I thought that the oil tank was made of stainless steel but he said no, it is an internally copper coated tank. The visible part under the wheel arch certainly is very clean and non corroded. It has the appearance of stainless steel. I have now checked the tank and believe it to be made of stainless steel albeit with a brass filler neck and maybe other connections. The so called rust was a dark sticky deposit around the top inside of the filler neck. The deposit was confined to the top 50mm or so. A few particles were present in the deposit that I could not identify but I doubt that they were rust. I checked the tank internals with a powerful torch and from what i could see it was very clean.
All help and comments will be appreciated. Thanks in advance.