If it's not air, or water, I don't know what it is. I'm a bit stumped.

Power steering fluid is cheap. Flush it until it's clear and then take it for a drive to see if it magically transforms again.

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- K.C.Adams

'77 300D Euro Delivery
OM617 turbo / 4-speed swap
404 Milanbraun Metallic / 134 Dattel MB-Tex

Current status:
* Undergoing body work

My '77 300D progress thread