Plug showing lean but acts like its rich.
 

Got a crossfire that i cant seem to get jetted.....ive gone from stock all the way to 135 main (at 135 it pops and spits at wot) and the plug always looks just as white as it did right out the box. the base of the threads are black at 135.

Right plug?

Everything else in good condition?

Trying to jet a poor running engine is a waste.

Have you checked your valve adjustment?

are you sure you are getting good fuel flow?

Good call. Could be a float issue.

Should be....its got a riding mower tank, clear 1/4inch lines, mower shut off valve and a big glass filter. lines and filter are always full.

That doesn't mean there's enough fuel in the carb bowl.

What's your float level set at?

How's the float needle look?

Needle looks good. No clue on float level..never have messed with it. Whats it sposed to be? I belive this carb has the short pilot.

Not knowing what carb you have, I can't say.

How about a pic?

Ill pull it off and get some pics tonight. All i know is it looks just like any other 150 carb but its 26mm on butterfly side and the slide is larger diameter. It came off of an older mid size carter brothers 150.