Marine Products

From the day nearly forty years ago when the first Guzzler® pumps were installed as onboard bilge pumps, the Bosworth and Guzzler names have become synonymous with quality and reliability. We still field calls from customers who have one of these vintage pumps on board and after years of service have decided its finally time to replace the diaphragm!

Boat manufacturers the world over use Bosworth Guzzler pumps and Sea-Lect® Y-valves and accessories because of their legendary reliability.

Whether you are a boat builder, a marine products distributor or a mariner who insists on worry-free and dependable bilge pumps and Y-valves, Bosworth is the name of choice.

Often imitated, but never equaled.

"If you haven't got a Guzzler, you still need a pump!"

See Marine Products Catalog to download a catalog of these products.

Product Videos

Post Your Video

Have a Guzzler® video to share? Send us your product video and we’ll post it on this web page!

Just email us a Youtube or Vimeo link or the actual video to

Frequently Asked Questions

Where does a check valve go in the inlet line?
Check valves are also called “foot valves”, because they typically are placed at the foot of in the inlet line. There they serve as a “one-way” valve to permit water to be drawn up to the pump, but to help prevent it from flowing backward either when the pump is performing its exhaust stroke or when it is not operating. In this way, the check valve helps to maintain the height of the water column in the inlet line, thus maintaining the pump’s “prime”. We recommend that you use a check anytime the pump lift (i.e., the vertical distance from the fluid source to the inlet of the pump) exceeds 12 feet.
What is the maximum pressure the pump will sustain?
Our pumps are designed to generate pressures up to a maximum of 20 psi.
Can a Guzzler be used to pump waste water from a boat holding tank?
Pumping waste from boat holding tanks (or any other sanitation tanks) is a perfect job for a Guzzler. Guzzlers are in widespread use for pumping in sanitation applications on boats, trains, lavatory service carts and portable sanitation systems.
Can I run Guzzler motorized pumps 24/7?
Guzzler pumps use continuous duty motors. However, the elastomers (i.e., diaphragms and valves) in a Guzzler pump will tend to fatigue and wear out over time.

Under factory testing, our black Buna-N diaphragms last on the order of 1 million cycles. While this may seem like a lot of cycles, keep in mind that a pump running 24/7 at 72 rpm will reach one million cycles in a little over 10 days!

Under operating conditions in which the pump is generating significant positive or negative pressure (i.e., vacuum), diaphragm life may be shortened. Additionally, the choice of diaphragm material will affect diaphragm lifetime. While our Buna-N diaphragms (made of an FDA-approved formulation of Buna-N) last on the order of 1 million cycles, our recently introduced santoprene diaphragm (off-white in color, also made of an FDA-approved material) can last in excess of 5 million cycles. You should inspect your Guzzler pump on a regular basis to look for signs of wear and tear on your pump diaphragm and its components.

What should I check if the pump stops working?
If your pump stops working, the first thing to check is whether there is a hole or tear in the diaphragm. If so, the diaphragm needs replacement. If there is no problem with the diaphragm, then check to see if the pump is able to create a vacuum to draw fluid up to it. Disconnect the inlet line and, with your hand directly covering the inlet flange, pull the handle up (or turn the motor on). You should feel a suction on your hand. If not, then remove the outlet flange (opposite the inlet), to inspect that the valve is operating properly and not obstructed by any material. Depending on the type of valve, material in the fluid that enters the pump may become lodged in the valve and prevent it from closing to make a tight seal against the flange. If this happens, then the pump will be unable to create a suction on the inlet side. After checking the inlet suction, disconnect the outlet hose and, with your hand covering the outlet flange, press down on the handle (or turn the motor on). You should feel exhaust pressure against your hand. If not, then make a similar inspection of the inlet valve.

If there is no material lodged in either valve, the valves may simply be old and no longer seating properly. If your pump is a “400” series pump equipped with flapper valves, a simple trick is to turn each valve around. Sometimes flapper valves can warp as they age and simply flipping the valve to change the side that seals against the flange allows the valve to operate properly again. (Note that you cannot do this trick with “500” flapper valves since they have a specific side that needs to face against the sealing flange.) If the pump is operating properly when disconnected from your hoses (i.e., if you feel the appropriate suction and exhaust pressure), then a next step is to check your inlet and outlet lines for any obstruction.
Is it better to mount the pump horizontally or vertically?
The horizontal-handle pumps and the vertical-handle pumps are completely equivalent in functionality. Which you choose for your installation is entirely a matter of which style of pumping action (“back-and-forth” for the vertical handle and “up-and-down” for the horizontal handle) is convenient for your use. Additionally, if you equip your pump with duckbill valves, you can mount your pump vertically, which changes the sense of handle action as well.
Are Guzzler motorized pumps submersible?
No, although the motors used in a number of the Guzzler pumps are available with water-resistant enclosure, they are not waterproof and should not be submerged.
What size pump should I use if my boat is 25 feet or less?
For boats under 25 feet, the Guzzler “400&rduo; series pumps should be fine for typical bilge applications.
If it’s not a good idea to let the pump run 24/7, how do I automatically control it?
Running a motorized Guzzler pump 24/7 will simply mean that you will have to replace the diaphragm very frequently. A better way to prolong pump operation is to activate the pump with a float switch so that it turns on when the fluid to be pumped exceeds a certain level, and turns off when it drops below a desired height.

Marine Products Catalog