Maintenance Services Static and Dynamic Balancing Maintenance Spare Parts Technical Support Foundry Menu Services Static and Dynamic Balancing Maintenance Spare Parts Technical Support Foundry Goulds 3171 Self-PrimingHeavy-duty one-piece shaft, External impeller adjustment, Available in a wide range of alloys, Open impeller designVapor-proof option: Choice of packing or mechanical seal to contain crankcase vapors.