Jabsco PAR-Max 4 Bilge and Shower Drain Pump, Four Piston Diaphragm, 3/4 in Hose Barb, 1/2 in Ports

Overview

The Jabsco 31705 is a PAR-Max 4 bilge and shower drain diaphragm pump for 12V or 24V DC boat systems, with configurations for the two common onboard voltage ranges. It moves up to 16 litres per minute, self-primes to 2.5 m vertical lift, and uses connections for 19 mm (3/4 in) bore hose.

Built around a four piston diaphragm pump, it is suited to moving grey water from shower sumps, pumping nuisance bilge water from remote pickup points, or circulating water through a livewell where a diaphragm pump layout is preferred over a submerged centrifugal pump. Dry-running capability, thermal overload protection, and a waterproof coating make it practical for damp lockers and service spaces when the motor is mounted in a dry, ventilated location.

Key features

• Two voltage options cover 12V DC and 24V DC installations without changing the pump range.
• Up to 16 L/min output for bilge, shower drain, and livewell circulation tasks.
• Self-primes to 2.5 m vertical lift, which helps when the pump sits above the collection point.
• Multiple diaphragm, four piston pump layout supports extended dry running.
• Connections accept 19 mm (3/4 in) bore hose for common marine plumbing runs.
• Continuously rated motor has thermal overload protection for longer duty cycles.
• Meets USCG Regulation 183.410, ISO 8846 MARINE ignition protection, EN 50081-1 EMC, and EN ISO 8849 electric bilge pump standards.

Variants

This 31705 range is offered in two voltage configurations for different DC electrical systems.

The voltage changes by variant. Verified shared details across the range include 19 mm (3/4 in) hose connections, up to 16 L/min output, 2.5 m self-priming lift, 4 m maximum recommended total head, the same 248 mm by 106 mm by 100 mm pump size, and thermal overload protection.

• 31705-0092: 12 Volt. This version matches boats with a 12V DC house or service circuit and is commonly used on smaller craft and many cruising boats.
• 31705-0094: 24 Volt. This version matches vessels with a 24V DC service system and keeps the pump on the same voltage architecture as other 24V onboard equipment.

Installation and setup

Mount the pump on a solid surface with the rubber grommets left able to absorb vibration. For vertical mounting, place the motor above the pump head so any leak from plumbing or fittings is less likely to drip onto the motor. Use proper hose clamps on the 19 mm hose connections and keep the suction side as short and direct as the boat layout allows.

Use wiring, fuse protection, and switching suitable for the selected voltage version. The 12V version is specified with a 15 A fuse, while the 24V version is specified with a 10 A fuse. Keep electrical joins above bilge water, protected from spray, and accessible for service.

Use cases on board

This pump is a good fit for shower drain boxes, remote bilge pickup points, and livewell circulation where a self-priming diaphragm pump is useful. It also suits installations where the pump cannot sit directly in the water, such as a service locker near the sump or a dry compartment close to the bilge line.

Maintenance and care

Keep the inlet side clear of debris and inspect the strainer and hose clamps during routine bilge or plumbing checks. After heavy use, a quick check for air leaks on the suction side is worthwhile because small leaks can reduce priming performance.