The new springs come with a factory greasy oil on them. Which is what you are never supposed to do; put greasy oil on your springs. Once on the car it's a little tricky to wash them as well as them need to washed to clean all that off but see if you can soap them down. You won't hurt the engine. I wash my engine frequently. Alternative ideas are to just let nature take its course and let the greasy oil wear away on its own (I did that) or use a prop rod (I have one for when needed).
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