Attwood Scupper Valve User Manual

Warning

Attwood marine hardware, navigational lighting, bilge pumps, and other
marine accessories are specified more than any other brand by America’s
best-known boat manufacturers as original equipment. Look to Attwood
for quality replacement parts and marine accessories.

SAVE THESE INSTRUCTIONS

Form Number 69247 Rev. B

03-10

Scupper Valve
3876, 3871

FEATURES:
The Attwood Scupper Valve is designed for boats with self-bailing
cockpits. It is designed to be mounted over existing thru-hull fittings
up to 2" (51mm). The Scupper Valve is a combination of a corrosion-
resistant retainer ring, screws, rubber flapper valve and gasket.
The rubber flapper valve opens outward to allow water to exit
and automatically closes to help prevent backwash from entering
the cockpit.

The Attwood Scupper Valve is to be mounted on the transom above
the boat's maximum water line as determined by the boat's draft at
the maximum loading as recommended by the boat manufacturer.

TOOLS REQUIRED:
1.

Drill and drill bit

Phillips screwdriver

INSTALLATION INSTRUCTIONS:
NOTE: The Scupper Valve can be mounted two ways: on the transom
above the water line (Figure 1), or the boat floor via thru-hull drain
fitting, hose, and cockpit drain (Figure 2).

Use the flapper valve as a template and place over existing
drain hole in the transom. Position it vertically with the "hinge"
on top, while the flapper freely opens from the bottom
(Figure 3).

Figure 4 (3871)

Note: when using the 3871 Scupper Valve for transom
mounting, you must use a second retainer ring, #910881a, to
back-up the flipper valve (figure 4). This part can be purchased
separately.

ATTWOOD LIMITED WARRANTY
Attwood Corporation, 1016 North Monroe, Lowell, Michigan 49331 (“Attwood”) warrants
to the original consumer purchaser that Attwood brand products will be free from
defects in materials and workmanship under normal use and service for one year from
the date of original consumer purchases.

This limited warranty is not applicable if the product has been damaged by accident,
improper installation, unreasonable or improper use, lack of proper maintenance,
unauthorized repairs or modifications, normal wear and tear, or other causes not arising
out of defects in materials or workmanship.

Attwood products are warranted for use on pleasure boats. Any other use—including
but not limited to commercial, racing, or non-marine use—are not covered under this
warranty. Attwood’s obligation under this warranty is limited to repair of the product at
Attwood’s plant or replacement of the products at Attwood’s option without expense to
the original consumer purchaser. Any expenses involved in the removal, reinstallation
or transportation of the product are not covered by this warranty. The product must be
returned to Attwood’s plant at the address above, postage pre-paid, and insured with
proof of original purchase including date. If Attwood is unable to replace the product
and repair is not commercially practical or cannot be timely made, or if the original
consumer purchaser is willing to accept a refund in lieu of repair or replacement,
Attwood may refund the purchase price, less an amount for depreciation. The
acceptance by Attwood of any product returned or any refund provided by Attwood
shall not be deemed an admission that the product is defective or in violation of any
warranty. Products that are replaced or for which a refund is issued become the
property of Attwood.

This warranty is Attwood’s only expressed warranty of these products. No implied
warranty including, without limitation, the implied warranties of merchantability and
fitness for a particular purpose, shall be extended beyond the warranty period stated
above for each product. Attwood shall not be liable for any damages, for loss of use of
this product, nor for any other incidental or consequential damages, costs, or expenses.

Some states do not allow limitations on how long an implied warranty lasts or the
exclusion or limitation of incidental or consequential damages, so the above limitations
and exclusions may not apply to you. This warranty gives you specific legal rights, and
you may have other rights which vary from state to state.

Mark holes and drill to accommodate #6 x 1" (25mm)
self-tapping screws.

Mount the gasket over the drain hole, the flapper valve over
the gasket, and then the retaining ring over the flapper valve
while aligning the screw holes. Fasten and tighten screws.

DO NOT OVER-TIGHTEN

WARNING:

The Attwood Scupper Valve is to be mounted only above the boat's
maximum load water line as determined by the boat's draft as
recommended by the boat manufacturer.

Figure 2

Figure 1

Figure 3 (3876)

(3876)

(3871)

Gasket

Flapper Ring

Retainer Ring

Maximum Water Line

•

Drain Hole

Transom

910881A

Spacer Ring

Cockpit

Cockpit Drain

•

Clamps

Scupper Valve

Maximum
Water Line

Thru-Transom, Thru-Hull
Connector, Part# 3875B

Hose

•

#6 x 1" (25mm)
Self-tap screw

Retainer Ring

Flapper Ring

Gasket

"Hinge"

•

910881a Spacer Ring for #3871
Transom Mounting (sold separately)