Jabsco Par-Max 3 Fresh Water Pump 31395-4012-3A - 12V, 3 GPM, 40 PSI Self-Priming

The Jabsco Par-Max 3 is a 12V fresh water pump built to bring home-style water pressure to a boat's onboard plumbing. A pressure-controlled diaphragm delivers on-demand flow through an integrated sealed pressure switch, so the pump cycles on automatically whenever a tap or shower is opened and shuts off when it closes. The pump is self-priming and can run dry without damage to the unit, which protects it if the tank runs low or a line loses prime.

An enclosed motor design gives the pump a long working life even when running at higher pressures, while an integrated bypass module reduces cycling and smooths out flow at the tap. Dampening feet under the housing absorb vibration so the pump runs quietly below decks. Plumbing connections are simplified with quick-connect ports: the pump ships with an inline 40 mesh quick-connect strainer to catch debris before it reaches the diaphragm, along with 2 x 1/2 inch quick-connect straight hosebarb fittings for fast hookup and servicing.

Rated for 3 GPM (7.6 LPM) of open flow at 40 PSI, the Par-Max 3 suits boats and RVs with multiple freshwater outlets that need consistent pressure across sinks, showers, and washdown points.

Specifications

• Brand: Jabsco
• Manufacturer Part Number: 31395-4012-3A
• Product Style: Submersible
• Voltage: 12 Volts
• Maximum Flow Rate: 3 Gallons Per Minute (7.6 LPM)
• Maximum Pressure: 40 PSI
• Quick Connect Strainer: Inline 40 Mesh
• Hosebarb Fittings: 2 x 1/2 inch adapters
• Product Dimensions: 9.09 inches L x 4.21 inches W x 4.21 inches H
• Weight: 5 pounds
• Material: Plastic
• Color: Black
• Power Source: Corded Electric
• Warranty: 1 year
• UPC: 671880841801

Frequently Asked Questions

What flow rate and pressure does the Jabsco Par-Max 3 pump deliver? The Par-Max 3 (31395-4012-3A) delivers 3 GPM (7.6 LPM) of open flow at 40 PSI, making it suited to boats with several freshwater outlets running at once.

Is this pump self-priming? Yes, the 31395-4012-3A is self-priming and can run dry without damage to the unit, so a low tank or momentary loss of prime will not harm the pump.

What voltage does this water pump run on? This Jabsco fresh water pump operates on 12 volts, the standard supply for most boat and RV DC electrical systems.

How does the pump turn on and off automatically? An integrated sealed pressure switch gives the Par-Max 3 on-demand operation, cycling the pump on when a tap opens and off when pressure builds back up with the tap closed.

What are the dimensions and weight of the 31395-4012-3A pump? The pump measures 9.09 inches long by 4.21 inches wide by 4.21 inches high and weighs 5 pounds.

What is the pump housing made of? The Par-Max 3 uses a plastic housing in black, which helps protect the motor from corrosion in a marine environment.

What fittings and strainer come with this pump? It comes equipped with an inline 40 mesh quick-connect strainer to filter debris, plus 2 x 1/2 inch quick-connect straight hosebarb fittings for hookup and servicing.

How does the Par-Max 3 compare to the Par-Max 2 pump? The Par-Max 3 (31395-4012-3A) is rated for 3 GPM at 40 PSI, while the Par-Max 2 is rated for 2 GPM at 35 PSI; both use the same quick-connect strainer and hosebarb fitting design, so the Par-Max 3 is the higher-flow, higher-pressure option of the two.

Will this pump run quietly below decks? Dampening feet under the 31395-4012-3A housing absorb vibration, and an integrated bypass module reduces cycling for quieter, smoother operation.

Does the enclosed motor affect the pump's lifespan? Yes, the enclosed motor design on this Jabsco pump is built for a long working life even when the pump is running at higher pressures.

What is included with the Jabsco Par-Max 3 pump? The 31395-4012-3A ships with the pump unit, an inline 40 mesh quick-connect strainer, and 2 x 1/2 inch quick-connect straight hosebarb fittings.

What warranty comes with this fresh water pump? The Jabsco Par-Max 3 fresh water pump, part number 31395-4012-3A, carries a 1 year warranty.