It is very hard to find competent Rotax service. My service told me that I can ruin the gearbox with this rough work, but when I asked them what's the solution - no-one knows, they told me the that rotax is engine will start rough ;-) .
As for your method: AFAIR mine won't start well the second time. But I will try tommorow.
And of course will let you know if cleaning changes anything.
I have posted one more message with link to youtube video with my engine, but admin did not accepted it yet.
edit: now you can hear how my engine works