Scott Danforth us right to recommend spray intake valves. Valvetect makes it for Serra, Quicksilver and Evinrude Johnson. I need help locating where to spray it. There is a mesh screen in front on the 5.3. Does that come off or do I spray through it. Any help is appreciated. I also think that I idled and trolled at too low rpm to burn off the carbon from the intake valves. So would that spray cleaning be a must for the VP 5.3 DGI Gen 4 motor. Does VP really want to admit to this in a Service Bulletin??
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