How do i tighten the nut (n) in the pic, i have taken the pin out but the nut needs tightening as there is about a 1.5mm gap between it and the bit it should tighten on to. Whenever i turn it the whole thread turns, is there a way of stopping the thread turning that i can't see or am i being thick. This was the only thing it failed it's MOT on today not even any advisories, so gotta get this sorted in 10 days for a free partial retest 
Any help much appreciated, TIA Nero
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Any help much appreciated, TIA Nero
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