My FS 56 was put away working just fine. The next day it would start and run but, it would not rev up. So, I replace the fuel no help. Adjusted carb no help. Major tune up no help. New carb no help. What on earth am I missing here?
Air, fuel, spark and compression. Good places to start. Find out which you are lacking.
SLOWLY hit the primer. Does it fill up the bulb with fuel? Don't smash it like you are trying to draw blood. It will bring more air into the carb. Primer bulb should draw mixed fuel from the tank sending it to the carb. Overflow hose from carb goes back to the tank. Bulb should be darn near full of fuel.
New Stihl carb with the same part number as you replaced? Or some Chi-na' carb that you saved a whole bunch of money on?
Could have a cracked fuel line, clogged fuel filter, dead spark plug, plugged up U.S Forestry spark arrestor screen and maybe some seals. Ignition coil, sheared flywheel key........
#3
ILENGINE
First thing I would check is the outlet to the exhaust. Something may of built a nest in in obstruction the outlet. Also could be carbon buildup on the exhaust screen which would allow it to start and idle but not rev up.
#4
Craftsman Garage
Clean your carb
#5
StarTech
What IL is referring to is item #3 held in by item #4 screw. These do become clogged with carbon and they can be difficult to get out. These spark arrester screens are there to help to prevent fires. Once the screen is out you simply heat it up and burn the carbon off.. Also as mention mud dabbers like plug these up too but not as easy as other designs.
