Having some issue with my 90 horse Merc. Motor will crank right up, idle fine and will run all day long until I cut it off. I mean it will run great at low RPM's, full throttle or however want to run. If I ever shut it off it will not crank back up. It seems like a fuel delivery issue. I can wait about 30-45 minutes and it will finally crank up, but will idle rough and struggles to get going. It will finally pick up and run great again whether wide open or just putting along. I had some gas from last year still in the tank so I drained it and put fresh gas it. I didn't really think that was the issue, but I just wanted to eliminate it. I have replaced both fuel filters, plugs and all four coil packs and it still does the same thing. The plugs that I took out were dry and didn't seem fouled. They had a white to greyish residue on the electrode, but that seems normal. The crankcase does seem like it is a little over filled, but it doesn't seem to have any gas it in or at least it doesn't smell like it. I just can't figure it out. My next step is to open up the FSM and replace the float switch and high pressure pump. Any ideas? Am I on the right track? Does this sound like a vapor lock issue? Thanks.
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