Hello tiger,
With your starter, if the single lug that engages the starter cup is not throwing out when you pull the cord, I would strip and clean it.
If you have done other starters, it wont be too much different.
Undo that centre nut and it will all come apart.
If you just want a quick fix to assess your engine, spray some WD40 inside, it should throw out enough to test your engine.
Oh, I also inspect the lugs inside the starter cup for wear, I have doctored them up with a file in the past.
Cheers
