FUEL PUMP MEMBRANE 84141M

Function and technical context

The 84141M fuel pump membrane acts as a diaphragm in the fuel system of Mercury and Yamaha marine engines, regulating fuel flow and pressure through precise oscillating movements towards the carburetors or injectors. This component is critical within the petrol distribution system, since its wear or deterioration causes unstable fuel pressure that results in misfires, loss of power or unexpected stops during navigation. The reliable operation of this membrane is essential to guarantee constant power and prevent the engine from suffering performance fluctuations or being affected by an unbalanced air-fuel mixture.

When to replace this part?

You should replace the membrane when you detect symptoms of progressive weakening in fuel pressure, such as difficult starts, irregular operation at low rpm, or noticeable loss of acceleration under load. Also if you notice internal leaks in the pump, excessive condensation in the fuel tank, or if the engine shows a sustained loss of power with no apparent cause in the spark plug or air filter. It is recommended to preventively check and replace this membrane during each seasonal maintenance or before any intervention in the feeding system, thus avoiding costly breakdowns at sea.

Mercury/MerCruiser

Equivalent manufacturer part numbers