Stihl FS38 pull string issue

[Linx_Prime]

Good morning. I have Stihl FS38 trimmer that won’t start. The pull string moves slightly with a spark plug in, and freely once the spark plug is removed. I have replaced the old spark plug and it still does this. Any suggestions on what to do? Thanks!

 

[Romore]

Do you frequently run the machine at part throttle as many do? There could be a heavy carbon buildup on the piston. What color was the tip of the old plug?

 

[Linx_Prime]

Do you frequently run the machine at part throttle as many do? There could be a heavy carbon buildup on the piston. What color was the tip of the old plug?

Thanks for the response.
It was black. Possibly flooded

 

[Hammermechanicman]

Put switch in stop position. Remove spark plug. Turn unit till spark plug hole is facing down. Pull starter rope vigorously a dozen times. Put spark plug back in. Do not choke it and try to start unit. If still can't turn engine over check to make sure using correct plug and that piston is not hitting spark plug. If still can't turn engine over probably got a serious carbon problem.

 

[Linx_Prime]

Thanks again for the reply. I will try turning it over and see what happens