Penny,
I just had the exact same problem with mine a couple of days ago.
Mine was the Reed, Valve
Quick test is take off the carb for the left hand side reach inside and make sure all 4 covers of the reed valves are still there. If you have a mirror and flash light, you can slide the mirror so you can see down the intake and use the light on the mirror and you can see it.
Becareful if you have to take the allen head screws out because I busted my nuckles on two of them and ended up stripping out the head of one, but we are all back together and running great.
I am not sure what causes them to break a friend of mine said it could have been a backfire or soemthing but I am not sure about that I think maybe it just wore out or something.
Let me know if this helps.
Thanks
TLF
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