... . Structure explanationPNJ, PNJFA-plastic pump parts and components are the main body, covered pump, impeller, the axis, the former sheath ... , after the sheath, brackets, vice impeller or packing seals,etc.Pump body, covered pump, ... to identify partslack of pump lift1. Impeller with the sheath is too large gap2. Impeller serious wear1. Adjustment the ...