Mark 25 Fuel Issues

[20mercman]

The contact rod on the throttle lever should be straight up and down. Sometimes the base could be bent, but make sure that the throttle rod is long enough to fully contact the cam on the magneto. I had one that slipped under the cam, and held the motor in a near WOT position and I could not slow it down. I threw on the choke, and was able to kill it, but could have been a real issue!

[cheetahgod]

Yeah the base is bent.

[cheetahgod]

What should idle rpm be?

[dave-bernard]

about 600-750rpm in gear.

[cheetahgod]

Thanks Dave
I adjusted float lever several times and was still running Rich. Adjust carb spring and now it’s running too lean

[dave-bernard]

check seals and intake port gaskets

[jeff-register]

Any failure in the fuel system, if not corrected will bite you. They MUST be very clean. You found the weak link. Replaced the needle But did you set the float correctly?

[jeff-register]

I assume before even trying to start " tinker toys" has already been there & inspect,

[cheetahgod]

What do you think?

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[jeff-register]

that’s an easy one, The float or needle need to be checked for level & drop, You are now delivering fuel but found the weak link. Merc’s have close tolances to run right. That’s what I liked about them, a challange! 😯

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