Marine Electronics Reviews
Bilge Pumps, We Rate Under 400 GPH Pumps

Bilge pumps from three makers, Rule, Whale, and Shurflo each have a pump fitting this flow category; all are rated at less than 400 GPH.

Shurflo Piranha 380 Bilge Pump

Both the Shurflo Piranha 380 and Rule 360, model 24 have vertically orientated motors and snap-on bases designed to mount on a horizontal surface.

The base on each unit acts as a debris screen to keep any foreign objects in the bilge water from entering the pump inlet and jamming the motor. The Shurflo 380 also has a swivel base and a screw-in motor cartridge, the latter feature makes debris removal easy.

Whale’s Supersub SS3612 pump is fitted with a horizontally mounted motor, this arrangement yields a very low profile. The base is designed for either vertical or horizontal mounting. The motor on the Whale pump can be snapped out for easy debris removal. All three pumps possess the same standard ¾-inch outlet.

Bilge Pump Performance

All did well in performance testing, with the Whale shining brightest. First off, they all passed our grueling 9-hour dry run test. In pump testing the Rule 360 managed an average flow rate of 290 GPH. The Shurflo did a bit better averaging 312 GPH. The Whale did the best with a flow rate average of 335 GPH.

All three pumps are equipped with AWG 16 tinned copper wire; Rule and Shurflo have the highest temperature and voltage rating on the wire insulation. Wire lengths run from 25 inches on the Whale, to 29 inches on the Rule, to a whopping 69 inches on the Shurflo. The Rule 24 is available with 6-foot leads as the model 24-6 adding about $2 to the cost.

Both the Rule and Shurflo pumps require a 2.5 amp fuse while the Whale uses a 3 amp. During our testing the Rule drew 2.2 amps, the Whale 2.5 amps, and the Shurflo only 1.9 amps.

Street prices in this pump size range from $15 for the Rule 24 to $17 for a Shurflo 380. The Whale SS3612 is a bit more money at $25.

Whale Supersub SS3612 Bilge Pump

We like the Shurflo Piranha 380 in this group; it topples the Whale with its longer warranty and lower price. It barely edged the Rule on performance.