... to prolong the using life, adopting the starting liquid to resisting rust,deteroprate, freeze,boiling(boiling point ... ,Removing all parts of cover,rings,carbon brush,brush box,brush box shell and short circuit ring equipment( ... to prevent the harm of inter parts or liquid leakage. it can not knock heavily, after ... its desing is maintenance free. 2,When the liquid is below than the requetment, it should to ...