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1984 Mariner 40 HP carb help please

M

motoXman700

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Carb problem Mariner 40 1984 with Yamaha engine. This engine is new to me and the settings were all off and I'm trying to correct it. I have completely disassembled the carbs, cleaned them and reinstalled them. The choke butterfly's were staying 3/4 closed with choke in off position and plugs were fouling up. The electric choke solenoid bracket was bent. I fixed that and now the butterflies are full open with choke off, full closed with choke on. Is this correct? I think engine is running LEAN, 20 min ride on the pond and my new plugs have no color to them yet.. In my experience with 2 strokes they should be showing color by now correct? The engine starts good, idles good, runs well on the lake... I am happy with the performance as is so long as I'm not LEAN. Any advise? Thanks
 
There should be some color on those plugs by now. Careful that you don't burn it up before finding out what's wrong there. I suspect a restriction in the fuel system, an air leak before the pump, or a bad diaphragm.

Jeff
 
Thanks. How about the choke setup, do I have it correct or should the choke butterflies remain partially closed with the choke off? Because I set them full open choke off, full closed choke on. This could cause a lean condition. I should mention the plunges were so gummy and black before I used this engine suggesting lean condition wasn't a problem before
 
Okay I'm out and about right now I have the idle screw mixtures set at 2 1/4 turns out. Spark plugs still look white they look lean to me and I don't know why. The motor otherwise seems to be running okay.
 
Spark plugs still look white...
Click to expand...
Snow white is lean...new plugs offwhite to beige would be normal...plugs will darken over time. Just to be safe add a little oil to the gas to run it at 40-45:1 ratio.
 
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