Mark - Nice work on the trusty Victa 2 stroke. Being a Cast Iron Block it would have stood up well to the additional heat!

Grumpy - Thanks for the explanation - I should have added the previous owner mentioned the mower was left running by their father inlaw in long grass. I suppose the additional heat and dry grass could have made it catch fire.

I am learning towards the grass in the mower being soaked in petrol - this particular mower was pretty clogged up full of grass.

I dont suppose you have any suggestions about removing the melted plastic? I was thinking of my multi-tool.

Jaffa