How To Install A One-Way Scupper Valve

By Dan Armitage
Published: Fall 2013

If you find your feet getting wet on your boat's self-bailing deck, something's amiss.

Here are the steps we took when installing one of two Flow-Max drains on a center-console boat:

Photo of removing the scupper assembly
Photo of filling original screw-mounting holes with selant
Photo of fitting the Flow Max base-mounting over the scupper hole

1. First, remove the original scupper assembly. See tools needed (see above).

2. Fill the original screw-mounting holes with marine-grade sealant.

3. Fit the Flow-Max base-mounting plate over the scupper hole and use the screws supplied to secure to the transom. In most cases, such as this, the plate's holes will align perfectly with those that secured the original scupper-valve mounting plate so no drilling is required.

Photo of securing the scupper bowl assembly to the base
Photo of using the locking screws supplied, securing the bowl to the base
Photo of completed assembly

4. Secure the scupper bowl assembly to the base with a twist-and-lock motion.

5. Using the lock screws supplied, secure the bowl to the base. All that's needed to clean the bowl is removal of the screws and twisting the ball unit free of the mounting plate.

6. Installation is complete.End of story marker

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