Five Oceans Fuel Line Primer Bulb for Outboard Motors — Large 3/8" Ethanol-Compatible, EPA/CARB Approved

The Five Oceans FO-4279 is a large 3/8-inch universal primer bulb that reliably primes outboard fuel lines and meets EPA and CARB low-permeation standards.

Designed for small boats and outboard motors, this primer bulb delivers a strong, leak-resistant feed to help start engines quickly. It includes barb-end connectors and stainless-steel hose clamps so you can install it on 3/8" inside-diameter fuel hose right away. Built with multi-layer, marine-grade materials, the FO-4279 resists weathering, UV exposure, and ethanol fuel permeation up to E85 blends.

How does this primer bulb help when starting a boat engine?

The FO-4279 creates suction and pushes fuel from the tank to the carburetor or fuel pump, reducing cranking time and avoiding dry starts. Its large bulb volume speeds fuel flow, and the one-way valves maintain prime between uses.

• Fast priming action for quicker engine starts
• One-way valve design prevents fuel backflow
• Large 3/8" bore handles higher flow demands

Is this primer bulb compatible with modern fuels and regulations?

Yes — the FO-4279 is EPA certified and CARB approved for low-permeation emissions requirements. The multilayer rubber construction is formulated to tolerate gasoline blended with up to 85% ethanol (E85), diesel, and biodiesel blends without premature deterioration.

• EPA-certified and CARB-approved for compliant use
• Compatible with gasoline, E85, diesel, and biodiesel blends
• Low-permeation materials reduce evaporative emissions

What’s included and how simple is installation?

The package ships ready for retrofit: an assembled primer bulb fitted with barb-style hose connectors and pre-attached stainless-steel hose clamps. Installation requires only cutting your 3/8" fuel hose to length, sliding the clamps into place, and tightening with a screwdriver.

• Comes with barb end connectors already attached
• Stainless-steel clamps included for a corrosion-resistant seal
• Fits 3/8" inside-diameter marine fuel hose; tool-required: screwdriver

How durable is the FO-4279 in marine conditions?

Constructed from multi-layer marine-grade rubber, the FO-4279 resists UV degradation, salt spray, and general weathering common to boating environments. Low-permeation inner layers limit fuel vapor escape while outer layers protect against abrasions and hardening.

• UV- and weather-resistant exterior for long service life
• Multi-layer design minimizes fuel permeation and swelling
• Stainless-steel clamps resist rust in saltwater use

Who is this for? The Five Oceans FO-4279 primer bulb is aimed at boat owners, marine technicians, and DIYers needing a compliant, ethanol-tolerant fuel-priming solution for outboard motors and portable engines. If you run a small to medium outboard, repair fuel lines, or outfit boats used in regulated areas, this ready-to-install, durable primer bulb offers a practical upgrade to maintain reliable starting and reduce fuel vapors.