Mercury - 5/16" (8mm) Fuel Line Assembly 8 Feet Fuel System Low-Permeation Gray Hose with Primer Bulb 8M0061891. OverviewEvery boater has had that one morning when the engine just does not want to wake up. You squeeze a tired old primer bulb, wonder if fuel is even getting to the motor, and feel the day slipping away before you ever leave the dock. Swapping to a proper Mercury Marine part like this fuel line assembly changes that story. The Mercury 8M0061891 fuel line assembly gives you a solid,