Damaged casing - any ideas ?

Give Dene a call at Two wheel engineering in Bridgend. 01656 760139
He will be able to sort it.

What about fresh chemical metal, if you hurry, splodge it on, then get a slightly longer bolt and nip the cap back on so the 'O' ring on the cap finds its own seat forming the chemical metal to its own needed shape, oil the o ring so it dont stick & also will help it to seat better. But again without seeing it, thats my idea..