i have noticed that when i take my pull start off the backplate and starter shaft and owb are all covered in thick black oil, where is this coming from and how can i solve it because the owb starts slipping when covered in oil.

Thats just the residue from the fuel just spray it out with wd-40 to clean it seal it up and keep running

Clean everything good, the pullstart, owb, and the backplate (don't thake it off)...

Then spray some wd-40 on the owb and put some silicone glue (shoe goo) around the edge of your backplate...

do you mean put the silicon glue in the edges where the backplate meets the engine

yes, there. and dont forget to soak your owb for a few hours in synthetic oil. 30wt. owb wont last long without oil