This is my final comment on this thread.
I have installed a new clutch in the line trimmer and after assembly the unit started right away. So the broken clutch was the cause of the hard starting and idling problems. It now takes only about 3 pulls to start and idles without stalling like it did before.
Had I known about this I wouldn't have spent money to purchase other parts so hopefully someone other than me can learn from this: A seized clutch could be the reason for hard starting and idling problems.
I wanted to thank all of you, specially to Grumpy, for all the help, guidance and for running such an excellent site!!
