Click to enlargeGROCO Backing Block f/2" & 2-1/2" Seacocks
Manufacturer: GROCOPart #: BB-3SKU: 74173
Item #: 74173
Category: Fittings
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Description
Backing Block for 2" & 2-1/2" Seacocks Features: Each size fits multiple seacock sizes Press threaded brass inserts into the hull side of the backing block into the holes that match the seacock flange Rigid 1/2" thickness provides secure installation but is flexible enough to conform to minor hull curvature Will not swell or absorb moisture Made from an environmentally friendly PVC foam specially formulated for marine applications
Specifications
| Brand | GROCO |
|---|---|
| Part Number | BB-3 |
| EverTide SKU | 74173 |
| UPC | 742985170155 |
Specifications are provided by the manufacturer. Confirm fitment for your application before ordering, or contact us and we'll help.
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Returns & warranty
Returns are accepted within 30 dayson items that are unused and in their original packaging. Some items may be subject to a manufacturer restocking fee. Special-order items may not be eligible — if you're unsure, ask us before ordering.
GROCO productscarry the manufacturer's standard warranty. For a warranty claim or a return authorization, see our full returns policy or contact us.
Marine Plumbing & Ventilation — frequently asked
- How do I size a bilge pump?
- Bilge pumps are rated in gallons per hour (GPH), but actual output is lower once you account for hose length and vertical lift. Choose a pump rated well above your expected worst-case water intrusion, and consider a second, higher-capacity pump plus a float switch for automatic operation.
- Can I use regular garden hose for my boat’s water system?
- No. Marine plumbing uses purpose-built hose rated for the specific system — potable water, sanitation, and raw-water/bilge hoses differ in pressure rating, temperature resistance, and permeation. Using the wrong hose causes odors, leaks, or contamination.
- Why is ventilation important on a boat?
- Ventilation clears moisture that causes mildew and rot, and — critically on gasoline boats — clears fuel vapors from the engine compartment before starting. Blowers, cowl vents, and dorade boxes keep air moving through cabin and engine spaces for safety and comfort.
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