#   Scepter Premium Fuel Primer Bulb | 8mm | Boat Parts for Repairs and Maintenance   RWB4721

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    $23.68  each

            Brand: [Scepter Marine Fuel Tanks & Accessories](https://www.rhsboating.com.au/brands-listing/scepter-marine-fuel-tanks-accessories.html)

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    ### Scepter Premium Fuel Primer Bulb | 8mm | Boat Parts for Repairs and Maintenance

Scepter Premium Fuel Primer Bulb - 8mm (RWB4721) is a replacement or installation option for the matching marine system. Solvent- and UV-resistant primer bulb with dual check valves. Suitable for petrol, diesel and ethanol blends.

Hose inside diameter: 8mm.

### Choosing and using this product

Match the primer bulb to the fuel hose inside diameter and the fuel used in the boat. A larger-looking bulb is not a substitute for the correct hose connection. Compare the listed barb size with the existing line, and check the ratings of the hose and connectors at the same time. The complete fuel assembly must be suitable for the intended fuel, even when one newly fitted component has a broader compatibility rating.

Before removing the old bulb, note the direction of fuel flow from the tank towards the engine. Follow the marking on the replacement and the installation instructions for its position and orientation. Leave the bulb accessible for normal priming and inspection without placing it where it can be crushed, stepped on or pulled sideways by a short hose. Support the adjacent line and avoid tight bends against the connections.

Work with the engine stopped and ignition sources removed. Keep dirt out of the open hose ends and use hose attachment hardware suited to the line and fuel service. Inspect the old hose for hardening, splitting or damaged ends; a new bulb will not correct a leak elsewhere in the supply. Replace damaged components with properly matched parts rather than trying to compensate with excessive clamping force.

Prime the system according to the engine instructions and check both bulb connections for leakage before starting. If priming remains difficult, inspect the tank vent, line routing and connections as part of the diagnosis instead of assuming the bulb is the only possible cause. Keep the bulb’s hose size and fuel compatibility details with the boat’s service notes so the next replacement can be selected accurately.

### Product details

- Hose inside diameter: 8mm
- Product code: RWB4721