I have replaced the belt on my Dyson DC04 several times over the years but now it just burns through straight away. The brush bar is not jammed but even with a new belt, the brush won't turn.
remove the drive roller and TRY to turn the end caps bet they are solid
remove and clean out the end caps on the ends of the brush roller, hairs are a nightmare twisted round the spindle ends put a drop of oil on the spindle ends refit the caps do they now turn EASIER if yes refit your belt
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