The Victa Corsair 2 stroke is having a problem starting. When the starting rope is pulled it sometimes makes a clunking sound but on some pulls it doesn't make any sounds however it still won't start. I had noticed that the washer next to the locknut holding the blade plate had broken in half and so I replaced it with another one from another Victa machine. Still makes a clunking sound when you pull the rope but I cannot get it to start. Any suggestions?