Jabsco Pump Catalog

Troubleshooting 1 SYMPTOMS • End faces hard and either polished or cracked, like carbon. • Some or all blades completely missing. CAUSE • Dry running, lack of water in pump. • Temporary suction blockage. • Leaking suction plumbing. REMEDY • Do not run pump for more than 20 seconds without liquid. • Install a liquid sensor/temperature alarm. • Check suction plumbing, strainers, and through hull fittings for blockages and leakage. • Arrange discharge plumbing to trap liquid in the pump. Troubleshooting 2 SYMPTOMS • Pieces missing from the middle of blade tips. • Blade edges are hollowed out. • Pitting is evident on cam and the inside of pump ports, and on ends of impeller. CAUSE • Cavitation, i.e., too much vacuum on inlet is causing water to boil inside pump. REMEDY • Reduce pump speed. • Increase inlet plumbing diameter. • Reduce inlet plumbing length and remove unnecessary restrictions. • Reduce cam thickness. Troubleshooting 3 SYMPTOMS • Worn blade tips, cam imprint on edges. • Worn end faces. • Worn impeller drive and shaft wear. CAUSE • Abrasive wear from fluid in pump. • Heat exchanger/cooler blockage. • High discharge pressure. REMEDY • Check discharge plumbing for partial blockages. • Increase discharge pipe diameter. 152 12 Impeller Replacement TROUBLESHOOTING GUIDE