Review on Amarine Made 12v Water Pressure Diaphragm Pump: High-flow, Versatile for Caravan/RV/Boat/Marine Applications by Phillip Jaylon

Didn't expect a bad experience with this product. Looks nice. Bought this pump to replace another pump in an existing installation for more GPM. Couldn't get it to work properly. After installation, the pump ran at the upper pressure limit. I isolated it from the shore line, there was no leak around the pump but I did hear a whistle in the pump itself. Tried the set screw, couldn't stop it from turning. All pump head screws tightened, motors at upper temperature limit. Apparently this pump is not working in any way.