I think the problem, if there is one, is in the fragility of the thin plastic aussietrev. In the position it is (downward-facing, completely shielded by the rest of the housing when installed on a mower) there will have been no sun damage, and that is what usually causes failure of plastics in Australia.
Please remember the warning in the instructions: unwind the cord to remove the tension from the spring before you take the cover off or do anything else, then remove the cover, but read the CAUTION part and wear safety glasses:
![[Linked Image]](https://www.outdoorking-forum.com.au/forum/uploads/usergals/2015/05/full-2772-22013-bs_vertical_pull_starter5.jpg)