Shopping from Canada? 
Go to Defender Canada!
Jabsco
Jabsco PAR-Max HD4 Marine Freshwater Delivery Pump
Item: #871044 | Part Number: Not Selected$154.99 - $248.99
Description
The Jabsco PAR-Max HD4 Marine Freshwater Delivery Pump delivers reliable, quiet performance for demanding onboard water systems. Built with heavy-duty materials and advanced TPV technology, it offers long life, smooth flow, and on-demand operation with dry-run protection. Ideal for marine freshwater delivery where durability and efficiency matter.
Jabsco PAR-Max HD4 Marine Freshwater Delivery Pump Item # 871044
Description
The Jabsco PAR-Max Heavy Duty Marine Freshwater Delivery Pumps are designed to be durable and high performing; providing years of satisfactory service in a variety of marine applications.
Features:
- Co-Molded TPV technology for long life and durability
- Efficient and quiet operation
- Heavy duty, motor and cast aluminum lower housing which allows for long-life, even at high pressure
- Integrated, sealed pressure switch for on-demand operation
- Self-priming allows for installation versatility
- Can run dry without damage
- Quick connect ports for ease of installation, servicing, and maintenance
- Vibration dampening mounting feet
- Equipped with integrated bypass module to reduce cycling and provide smoother flow
- Plastic housing protects the motors on these units from corrosion
- Includes fittings and strainer
Specifications:
- Internal bypass: Yes
- Open flowrate: 4 GPM (15.1 LPM)
- Max inlet pressure: 30 PSI (2.1 BAR)
- Motor design: Brushed, permanent magnet TENV
- Upper housing material: Fiber reinforced polypropylene
- Lower housing material: Cast aluminum
- Diaphragm: Santoprene
- Check valves: EPDM
- Fluid temperature range: 32° - 140° F (0° - 60° C)
- Certifications: CE, ISO8846, RCM
- Ingress protection: IPX6
Jabsco Par-Max™ Series Marine Freshwater Delivery Pump Data Sheet (2.64 MB)
Part Numbers for Jabsco PAR-Max HD4 Marine Freshwater Delivery Pump
Reviews
Rated 4 out of
5
by
Andy C Bermuda from
Wash away.
A great pump to work with. Quiet and dependable. Simple to install.
Date published: 2025-04-21
Rated 3 out of
5
by
Ryan from
Decent pump, not great.
The 40gph pump is definitely not what we had prior, this is barely a trickle of water. Fairly disappointed in the quality and flow. On top of that, delivery was very slow. Would I buy it again? No.
Date published: 2026-05-18
Rated 5 out of
5
by
Raffi from
3 months review.
Pump is still working as it should. A bit expensive, but might be worth it if I don't have to buy another one for a few years.
Date published: 2026-05-04
Rated 4 out of
5
by
Reel therapy from
Good pump
Good product works fine. I’m using as saltwater wash down.Wish it had more volume.
Date published: 2025-11-27
Rated 3 out of
5
by
Michael M from
It's Ok.
Purchased as a replacement to a discontinued 3 series Jabsco pump which lasted 13 years. This pump died a few months after install. Defender made good on the warranty and replaced the pump. Jury is out how long this will last. Works well for now.
Date published: 2025-10-16
Rated 4 out of
5
by
Brent from
Strong and responsive
This Par Max HD4 replaced a Marco variable speed pump that lost a bearing after 8 years service. The Jabsco pump is not variable speed but uses a bypass to regulate flow. Flow from the HD4 is significantly more than the Marco even though both are rated for 4 gpm. A pressure bladder was installed down stream of the HD4. The HD4 responds to keep the flow steady even when multiple faucets are in use. This steady flow improves operation of the instant hot water heater. Overall I am quite pleased with the Jabsco HD4. Minus one star for being louder than the Marco (very different technology). We won’t use this pump when someone is sleeping nearby.
Date published: 2025-10-06
Rated 5 out of
5
by
—— — — from
Water pimp
This was an exact replacement with all fittings lining up perfectly.
Thanks
Date published: 2024-08-01
Rated 4 out of
5
by
Anonymous from
Easy swap-out
Works great. Easy to install. Perhaps not the quietest, if that’s a concern.
Date published: 2024-06-26
Questions
Can you please tell me what the “cut-in” pressure is for the 4GPH 60PSI fresh water pump? I need to know this value for setting up the fresh water accumulator tank.
There is detailed information in the data sheet. https://defender.com/assets/pdf/jabsco/503908par-max_data_sheet.pdf
Date published: 2024-03-26
Hose connection size
1/2 inch ID hose. Believe you are able to buy 3/4" attachments separately, but it comes with barbs for 1/2" ID hose
Date published: 2025-12-18