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Attwood Shower Sump Pump System 750 GPH 12V | 4143-4

Original price $346.99 - Original price $346.99
Original price
$346.99
$346.99 - $346.99
Current price $346.99
Availability:
Only 1 left!

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Attwood 23-41434 corresponds to manufacturer part 4143-4, a 12V shower sump / shower pump system rated at 750 GPH. Current product listings identify it as a large-box sump system built for marine gray-water drainage from areas such as showers, sinks, galleys, bilges, and heads.

This system is designed to collect drain water in the sump box and automatically pump it out. Current references highlight a gasketed snap-on lid, air vent to help prevent air locks, straight mesh filter for easier cleaning, and pre-installed inlet fittings instead of a shared manifold, which makes service and installation more straightforward.

Key Features

  • Attwood shower pump / sump system
  • LNS SKU: 23-41434
  • Manufacturer part number: 4143-4
  • Voltage: 12V
  • Pump rating: 750 GPH
  • Large box sump design
  • 3/4" outlet hose
  • Choice of 3/4" , 1" , 1-1/8" , and 1-1/2" inlet sizes
  • 36" wire leads
  • Meets or exceeds applicable ABYC and USCG standards in current listings.

Compatibility / Application
Commonly used for marine gray-water drainage where water needs to be collected and pumped from a shower tray, sink, or similar low drain point. Current listings specifically mention use with up to 3 drains, including combinations such as a head sink, shower drain, and galley sink.

Fitment Notice
Please confirm the installation uses a 12V system, has space for the large sump box, and matches the required inlet and outlet hose sizes before ordering. This is best matched by sump-box size, hose routing, and drain layout rather than by engine model.

When This Part Needs Replacement
Replace this shower pump system when:

  • the pump no longer evacuates the box reliably
  • the float/automatic operation becomes inconsistent
  • the box, lid seal, or fittings are damaged
  • odor, standing water, or repeated clogging points to a worn sump assembly
  • a full sump-box replacement is preferred over piecemeal repair

Installation Notes

  • Confirm large-box sump dimensions fit the available installation space.
  • Match inlet hoses to the correct included inlet sizes.
  • The mesh filter is designed for easy removal and cleaning.
  • The slotted mounts help simplify installation and removal for service.
  • The air vent helps reduce air-lock issues in operation.

Replaces / Cross Reference Numbers

  • 23-41434
  • 4143-4
  • ATT 41434
  • 99-4012

Parts Desk Insight
On shower sump systems, the real selling points are usually serviceability and hose compatibility. This Attwood setup stands out because the lid, filter access, venting, and multiple inlet options make it easier to install and maintain than simpler sump boxes. That matters on boats where gray-water systems are used regularly and quick cleanup access saves time later.

Shipping: Ships same or next day for fast Canada wide shipping. ⚓

Shipping information

In-stock and OEM parts: ship same or next business day.

Locally warehoused items: ship within 3–4 business days.

Special-order items: timeline confirmed after order.

Returns & warranty

Returns & Satisfaction Guarantee

We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.

If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.

To qualify for a return:


  • Item must be in new, unused condition

  • Product must be in its original packaging

  • All parts, components, hardware, manuals, and accessories must be included

  • Packaging must be undamaged and suitable for resale

Important:

Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.

We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.

For return authorization, please contact our support team before shipping anything back.

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