"Rich" and "lean" refer to the air/fuel mixture. Rich means a higher proportion of fuel than is needed and lean means less.
An overly rich mixture can foul plugs, cause sluggish performance and promote carbon buildup in the combustion chambers, as well as decrease fuel economy.
An overly lean mixture can cause jerky, hesitant performance, overheating and in extreme cases even melt a piston crown.
Too rich and you will get black smoke from exhaust. You can also read the spark plugs. way too rich and the engine will bog down or flood out in extreme situations. If it's running too lean, the rpms will get erratic.
An engine runs by the combustion of a mixture of oxygen and gasoline. If this mix has too much oxygen, it is said to run lean. When the mixture has too much gasoline in relation to oxygen, it is running rich.
running lean can cause your 400ex to backfire ..if it backfires on deceleration its lean ...if it pops on acceleration its running rich.====carb issues
14.7:1 --- Air : Fuel Ratio. perfect. not lean, not rich.
YES it will. It will either run RICH or LEAN. Must repair.
it sense oxygen come out from your engine to tell the PCM your car is running rich or Lean
Base line for any machine is 32:1. If it seems your running rich, use a little less oil, and vice versa for running lean.
Rich is more face to face communications. Lean is e-mail. The less you interact with the audience the more lean you are.
saDS
this could be a number of reasons it could be your mixture screw or it could be running lean or rich the best thing to is a plug chop see what colour it is if its black and oily its running rich if its white its runing lean also if its running lean your engine will sound flat and could course it to seize or the main jet could be to big or to small its always best to over jet a a 2stroke and work down till you feel the engine getting better hence the bog going away hope this helps
How does it run? If it is running rich or lean then the carburetor could be the culprit. If it is original from 1986 I would bet it needs a rebuild.
That is a good possibility.It also could be running lean and causing it to smell that way.If it starts running poorly or wont accelerate then you will have to replace it. Need 2 find out why IT's running Rich.