Attwood Marine In-Line Fuel Demand Valve, For 3/8 in and 5/16 in Fuel Hose, Manual Override

Overview

The Attwood Marine 9300FDV7 is an in-line fuel demand valve for portable marine fuel systems that lets fuel move only when the engine is actually pulling it through the line. It installs between the fuel tank and the primer bulb, fits 5/16 in. and 3/8 in. fuel hose, and maintains flow up to 125 L/h with less than 2 kPa restriction.

On boats that use sealed portable tanks, pressure can build in the line before startup. This valve helps stop that fuel from being pushed toward the engine too early, which can cut down on flooding, fuel spillage, and the pressurized fuel slug that can hit the engine when the system is already under pressure. It also has a built-in manual override, works with ethanol-blended fuel, and is rated for operating temperatures from -4°F to 176°F with 20 psi nominal input pressure and protection for pressure spikes up to 40 psi.

Key features

• Fits 5/16 in. and 3/8 in. fuel hose for straightforward integration into common portable outboard fuel lines
• Installs inline between the fuel tank and primer bulb where pressure control matters most
• Allows fuel flow only on engine demand, helping reduce engine flooding and downstream fuel spray
• Low restriction of less than 2 kPa at 125 L/h helps maintain normal startup and running fuel flow
• Built-in manual override for added control when setting up or servicing the fuel line
• Composite body and ethanol-fuel compatibility suit routine marine fuel-system use
• EPA-certified and CARB-approved for pressurized portable fuel tank applications
• Compatible with OEM engine brands used across common outboard fuel-system setups

Installation and fit

This valve is a practical match for boats that run portable outboard tanks and need an inline valve to manage tank pressure before fuel reaches the engine. The main fit check is hose size and line layout: your system needs 5/16 in. or 3/8 in. hose and enough straight run between the tank connection and primer bulb for a clean installation.

For day boats, tenders, skiffs, and other small craft that spend time in the sun with fuel left in the line, this type of valve can help keep startup more predictable after the tank has built pressure at the dock or during transport. It also suits owners replacing a worn fuel-line valve and trying to keep fuel handling cleaner around the engine connection.

• 1336562_qbp913980.pdf

Shipping
We ship worldwide from the United States. Rates are calculated at checkout based on destination and package weight. Some items include free shipping, which will show automatically. Not every product is eligible for international shipping; checkout will confirm eligibility. We do not ship to PO Boxes except through USPS, and not all packages qualify.

Processing and dispatch
Most orders are verified, packed, and handed to the carrier within 1 to 2 business days. Some products may need extra handling time or ship directly from the manufacturer. For certain international orders, inventory transfers between warehouses may add time. If any delay is expected, we will let you know the dispatch date.

Delivery and tracking
Deliveries are handled by trusted carriers such as USPS, UPS, FedEx, and DHL. Estimated arrival times appear at checkout and depend on your location and the service you choose. These are estimates and can be affected by customs or carrier disruptions. A shipping confirmation with a tracking link is emailed when your order ships, and tracking may take up to 24 hours to update. You can also view tracking in your account.

Duties, taxes, and support
International customers are responsible for any customs duties, taxes, and fees charged by the destination country. If these charges are refused and a shipment returns to us, the carrier’s return cost and any re-entry customs fees will be deducted from the refund. If your order is late or you need help, contact cs@qualityboatparts.com and we will assist you.

Quality Boat Parts is a reseller. Many items include a manufacturer’s warranty, and all warranty service is handled directly by the manufacturer. We do not manage or administer warranty claims on behalf of customers.

Warranty terms, coverage, and duration are set by each manufacturer. Issues involving defects, repairs, or replacements must be addressed with the manufacturer’s support team. When available, the warranty period is listed on the product page. If it is not shown, contact us or the manufacturer for details before purchasing.

To start a claim, the customer must contact the manufacturer and follow their process. Keep your proof of purchase and original packaging, and register the product if the manufacturer requires it, as these are often needed for warranty service.

We are happy to help you find the right contact or documentation, but we cannot decide outcomes or intervene in claim resolutions. For guidance, email cs@qualityboatparts.com.