Posted: June 1, 2012
If an impeller pump stops working, you’re going to find trouble.You need your impeller pumps to operate at maximum efficiency, otherwise things start going wrong. JMP, a pump manufacturer (jmpusa.com), offers advice for keeping flexible impeller pumps in working order.
Pipe runs should always be kept as short and straight as possible, avoiding rising over obstructions, as this can create air-locks. Plumbing should be reinforced, non-collapsible hose of the recommended size. Also, flexible impeller pumps must not be run dry for more than 30 seconds. In particular, bilge pumps and water pumps should always be fastened to the boat structure to ensure they remain in place.
Flexible impeller pumps should be mounted so some water is left in the pump body when the pump is off, which will prolong impeller life and speed priming. The pumps’ overboard discharge must be well above the waterline to avoid water siphoning back into the vessel.