Overview

The Jabsco 18670-9407 is a 12V ballast pump that replaces MasterCraft 300249 and fits the original mounting position with the same electrical quick connector already installed. It uses a flexible impeller pump body with 1/2 inch female NPT ports and outside ports sized for 1 inch inside diameter hose, so it matches the plumbing layout commonly found in compatible MasterCraft ballast systems.

This pump comes with a green Run Dry impeller and is rated for continuous duty. It is self-priming up to 8 feet and moves 8.4 GPM at 10 feet of head, which gives a clear baseline for ballast fill and drain performance on a 12V setup.

Ignition protection to USCG 183.410 and ISO 8846 makes it suitable for gasoline-powered boats where the pump is mounted in enclosed spaces. This is a good match for owners replacing a failed factory ballast pump and wanting the same connector, the same mounting pattern, and the same hose size at the pump.

Key features

• Direct replacement for MasterCraft 300249 with the same electrical quick connector and mounting pattern
• 12V DC pump rated for continuous duty
• Green Run Dry impeller fitted from the start
• Self-priming up to 8 feet with 8.4 GPM flow at 10 feet of head
• 1/2 inch female NPT ports with outside ports that accept 1 inch ID hose
• Ignition protected to USCG 183.410 and ISO 8846 for gasoline-powered boats
• Works best with 1 inch ID hose and should not be paired with hose smaller than 3/4 inch

Installation and setup

Installation stays close to the factory layout. The mounting pattern matches the OEM unit, so there is no need to drill new holes, and the preinstalled connector lets the pump plug into the existing wiring on compatible boats. Using 1 inch inside diameter hose at the pump helps maintain the flow this unit is built to deliver.

The ports also include 1/2 inch female NPT threads, which helps when the plumbing uses threaded fittings instead of slipping hose straight onto the outside barb. Keeping some water in the pump body after installation helps wet the impeller and supports easier priming on the next cycle.

Compatibility and onboard use

This pump makes sense when the boat already uses MasterCraft part 300249 and the goal is to restore the original ballast function without changing the wiring or pump location. It fits 12V systems and suits wake and surf boats where ballast response matters every time the tanks or bags are cycled.

The bronze pump body and flexible impeller layout are practical for ballast water service, where small debris can make its way through the system. On gasoline-powered boats, the ignition-protected motor is an important detail when the pump is mounted near other equipment in enclosed compartments.