Ryobi Troy Built

my 4 cycle troy-built will not prime.Runs with start fluid.Prime bulb not filling.Whats wrong? John?

Tiller uses the 26cc mini 4 cycle ryobi engine.

Clean the fuel filter if dirty. Put in fresh fuel. Pump the primer bulb. Check for leaks. Replace bulb or fuel hoses if needed. Refer to Owner's Manual for information regarding carburator and choke settings. Make sure settings are correct. Remove, clean, regap, and reinstall spark plug or replace with properly gapped new plug. Clean and dry the air filter (probably an oiled sponge type of filter). Before reinstalling the cleaned air filter, pump up the bulb primer (it does not have to "get hard") and check to see that fuel is reaching the carburator. If you cannot tell, remove the spark plug and the fuel should be evident. If it is, reinstall the spark plug and start the motor. It should start. If does, let it run and spray some carburator cleaner into the carburator while increasing the engine rpm's. Give it several shots of cleaner to remove the "shellac" inside the carb. Reinstall the air cleaner and fine tune the idle and throttle settings. You should be good to go.

If it still won't run, you probably need either a carburator rebuild kit or a new carburator. If you are not comfortable performing either fix, take it to a lawn mower repair shop and pay to have someone else fix it.

Good luck.