Mercury - Primer Bulb with Hose Clamps Fuel System Component Rubber Composite 8M0061875. Overview. There's something reassuring about a fuel system that responds the moment you need it. When you squeeze a primer bulb and feel that firm, solid pulse of fuel heading toward the engine, it sets the tone for the whole outing. You know the day is starting off right. The Mercury Marine part 8M0061875 Primer Bulb brings back that quiet confidence-smooth, dependable, and ready every time you reach for it