You're not going to hurt anything. But I think the actual answer to your original question is... there is no answer... lol. They don't really have any kind of typical life. Some stick open, some stick closed, some last for eternity. Kudo's to you for doing preventative maintenance though.

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68 280SL - 70 280SL - 70 300SEL 3.5 - 72 350SL - 72 280SEL 4.5 - 72 220 - 72 220D - 73 450SL - 84 230GE - 87 200TD - 90 190E 2.0 - 03 G500

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