Running very rich and missing

Grassman69

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I hope someone has an idea for me. I have a 2018 RTZ L54 KH FAB that is driving me crazy. It suddenly runs very rich with black smoke and misses. I have changed the filters, plugs, fuel filter and pump, coils, checked it didn't skip timing, checked valve lash, and new carburetor with new solenoid all to no avail. Strange thing is when I disconnect the kill wire from the coils and shut off the ignition it runs better. Not good but better. Help
 

mechanic mark

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Check air filter for replacement. Pull dipstick & see if you have gas in oil.
 
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Grassman69

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No. Oil is good. Can't find anything mechanically wrong
I did however find I have no continuity on the ignition switch between L and A2 in the reverse position. Any thoughts ?
 

slomo

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Pressure test carb. Specifically the needle and seat here. Carb needle should hold 7psi for 30+ minutes with a WET needle. Spray some PB Blaster on the needle first.
 

slomo

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All those "new" parts will require testing.

Hope you are keeping your old parts. Most are probably good.
 

StarTech

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One question out curiosity. Does the ignition switch itself graphics on it of a mower in reverse? Someone could install the wrong switch.

But this has nothing with the running rich problem.
 
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