It is clearly loose and probably rusty. To be honest if I were you I would take it to someone who knows how to service it rather than try and do it yourself, and perhaps get them to teach you how it works so you can maintain it in the future.
@adroit started
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It is clearly loose and probably rusty. To be honest if I were you I would take it to someone who knows how to service it rather than try and do it yourself, and perhaps get them to teach you how it works so you can maintain it in the future.