Buy this degreaser
https://www.screwfix.com/p/no-nonsense-heavy-duty-degreaser-5ltr/88668
(I use it to clean bike chains and components, very effective)
Soak them for an hour or so agitating them with a brush.
Rinse them with boiling water, then dishwasher.
If they still smell, rub them with lemon, leave them for a couple of hours, then dishwasher again.
Been using it for years on bike components which are mainly aluminium.The Q&As say do not use it on aluminium.
functioning
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