One job specified before we can go flying is to make and fit these little things.
It took all day to design, make and fit them, but they were very satisfactory when done.
They fit onto the engine like this, and are an additional safety feature.
What are they for?
Well apparently the pushrods are prone to fatigue cracking at the threaded part you can see here. When that happens, centrifugal force swings them outwards and they trepan their way through the cowling, neatly removing the whole of the front end, which then gets thrown about and causes all sorts of other excitements, depending on how it breaks up and which direction it’s thrown.
You can see the sort of thing here.
These keepers should limit the damage to the single pushrod.