We have a Husqvarna Rider, model YTH180. It's

check for a small filter at the needle and seat connection
check for blocked main jet
check to see if fuel is running past the needle and seat when the top is off the carby

Check the Idler pulley to see if the spring is loose. If it is replace now before it lets go.. Its easier to do now than later.

Check your blade belts.

their are a few different filters for your rider --these are for the kohler 26 hp motor stores like home depot- lowes- sears- or small engine repair shops carry filters K&N PS-1002 http://www.sears.com/ayp-genuine-ayp-part-578416804-oil-filter-kohler-cou/p-SPM8242278631?redirectType=SKIP_LEVEL http://www.knfilters.com/oil_filter/all/kohler/sv735/26hp

sounds like the jets in the carb a dirty

first check for power going to the solenoid on the bottom of the carb its a anti backfire valve if you have power there when the key is cranking and when turned on the solenoid might just be stuck if that works maybe the gas that was left in the carb turn bad

Email me your model number of your mower. [email protected]

readjust the intake and exhaust valves every 300 running hours to elimanate this problem

That is certainly fuel related. This may be due to (1) a clogged fuel filter, (2) restriction in the pick up or (3) an improperly vented fuel cap.
Change the fuel filter. Completely drain and clean all fuel lines. Check the tank pick up for blockage. Completely drain, clean and refill tank with fresh gasoline.
Make sure air filter is clean.
If none of these steps are successful, then I would suspect the carburetor.
Otherwise contact your local service center or directly here:

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