I have a mercury 70 hp ser #4994943. It ran excellent down at the coast and when I moved up north to 3000+ feet elevation it bogs down and does not wind out like it used to. Compression is all equal 120+ psi at each cylinder. The main jet is 0.086 and the pilot jet 0.066. My manual (which is miss-placed) if my memory is correct said to go to 0.084 to main and 0.064 for the pilot jet. I had my wife go into town to order these and we accidently got the exact same size jets. I figure this jetting problem will solve my bogging and winding out to full rpm. Also I notice the carb throats are oily and the engine plus the inside of the engine cover. It used to be so clean and dry inside before. So who thinks this is a jetting problem? The merc dealer here says he does not think so but the main merc dealer down at the coast said to go with a leaner set-up as a first step. If someone here has the manual can they clarify my jet size for 3000' + elevation.
Thanks, Corey
Also on weeknd I saw a guy with an old 85 HP merc. He was from the coast and having the same problems.
Thanks, Corey
Also on weeknd I saw a guy with an old 85 HP merc. He was from the coast and having the same problems.
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