Supper LT1554 will only run with the choke on then it runs real rough

SOURCE: my 14hp 42

Sounds very much like a blocked main jet.
Pull the bottom of the carby while holding your hand cupped under it.(turn fuel off first)
If you find water drops, that is your problem.

If not,
Find the main jet.
Usually brass and in the center.
Look straight up into the carby and unscrew it with a smallish flat blade screwdriver.
Hold it up to the sun, you should be able to see a nice clean little hole.
If it is blocked, clean it with a wire from a wirebrush. Be gentle, if you damage it, you will never get it to run nice.
Clean every part carefully before re assembly.
Turn the fuel on and mow, mow, mow. :)

SOURCE: MTD Riding Mower with 21 hp OHV 1/C

the valves need adjusting

SOURCE: i have to close the choke for it to stay running

your cutting the air flow off to the carburetor allowing more fuel in, check all fuel lines, and filters, and fuel pump if you have one. If all ok than your going, to need to flush the int-ir fuel sys (clean). replace your fuel filter, and over haul the carburetor. replace your plug and oil too. Use a good aerosol carburetor cleaner. After your done use fresh fuel (stabulized). adjustment may be needed to the carburetor. Some Carburetors Are EPA and no adjustments are needed except idle screw. good luck I hope this helped.

Dennis Key

• 2481 Answers
• Posted on Mar 10, 2012

SOURCE: my briggs and stratton mower runs rough but when I toggle choke on and off it runs better for awhile

have to use choke means fuel problem. Check your fuel cap vent, fuel filter. Fuel solenoid opening with key turn on. Remove hose from carb.and see fuel runs out.

SOURCE: john deere LT180 runs rough and must use the choke to stay runing, what should I do?

remove the carb take it apart and soak in in carb cleaner for 24 to 36hrs clean out all the passages and that should do it