Mercury - Primer Bulb Fuel System Component Rubber Composite 8M0061876. Overview. Every boater knows that the day goes smoother when your engine fires up without hesitation. There's a simple comfort in squeezing a primer bulb and feeling that steady pulse of fuel heading toward the motor-no guessing, no struggling, just clean, reliable pressure. That's exactly what the Mercury 8M0061876 Primer Bulb delivers. It's one of those small but critical pieces that gives you confidence each time you head