Hi, I am John Mc, a Mercury dealer tech. I hope I can help you quickly and accurately. One moment while I work on your problem.
The pcv valve is located in the center of the engine under the intake on the throttle body side. Best way to find it is to follow the large vacuum line at the body of the throttle body that goes to it. Give me a sec and I'll post the instructions on how to replace it.
Click here for instructions
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