So I went back to the carburettor and, with the help of that video in the thread you referred to, this jet appears to be blocked. I don't have the right jet drill or whatever they're called so I tried some very thin stripped tie-wire and it seems to be well blocked. I also tried a pin and same result. I wonder what size it is?
I'm glad I found out where the PCV valve lives as that will help with future repairs.
![[Linked Image]](https://www.outdoorking-forum.com.au/forum/uploads/usergals/2015/04/full-1794-21198-imgp0711.jpg)
The blockage is at the small hole in the end. It's not visible in the photo.