Does it feel like there is any resistance there when you operate the lever??
Check the adjustment of the cables......
Check the levers on the rear Brake Backing Plates ....are the ends of the brake cables even connected!! are the levers all frozen up (pull the cable or try to move the levers at the backing plate)
Check (with a helper) with one drum off that the shoes are moving outward when the lever is pulled
However, sounds to me like your rear brakes are probably just worn down too low or are not correctly adjusted
[EDIT: Doc, Gaf...dunno what happened there...me no like being echo man!! when I posted there was nuttin there
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