0385784 0438559 OMC Fuel Pump | Genuine Used Part

🔧 Product Description

Genuine OMC Johnson / Evinrude Mechanical Fuel Pump - Current Part Number: 0438559

A genuine pulse-operated diaphragm fuel pump for selected Johnson and Evinrude carburetted two-stroke outboards. Current service number 0438559 replaces earlier pump 0385784. This is a fuel-only pump and does not meter oil, making it suitable for non-oil-injected engines and correctly configured pre-mix conversions.

⚙️ Key Features

• Genuine OMC mechanical diaphragm pump
• Current service number 0438559
• Supersedes 0385784
• Pulse-operated fuel-only design
• Broad small- and mid-range Johnson / Evinrude application family

🚤 Compatibility

• 1977 Johnson / Evinrude 85HP and 140HP applications using 0385784
• Selected 25HP and 35HP carburetted two-strokes using later 0438559 service configurations
• Selected 105HP and 115HP engines documented in late-1990s and early-2000s catalogues
• Broad service-family range: approximately 25HP-140HP
• Documented application period extends from the late 1970s through early 2000s
• Exact fitment is controlled by pulse-port position, hose orientation and engine fuel-system diagram

🔌 Function

Crankcase pressure pulses flex the internal diaphragm, drawing fuel from the tank and delivering it to the carburettors at low regulated pressure.

⚠️ Common Signs of Failure

• Engine starves for fuel at higher RPM
• Primer bulb collapses or will not remain firm
• Fuel leaks from diaphragm vent or body
• Pump will not draw fuel after storage
• Engine surges or stalls under load
• Pulse hose is split, blocked or disconnected

🔄 Supersession & Cross Reference

OEM Supersession Chain

• 0438559 → Supersedes 0385784
• 438559 and 385784 are unprefixed OMC number formats
• 0433390, 0388555, 0398385, 0395712, 0395718 and 0383765 are related earlier pump references within the same service family
• 0765591 and 5005462 are later related BRP service references used in applicable replacement catalogues

OEM / Related Numbers

• 0438559 / 438559
• 0385784 / 385784
• 0433390 / 433390
• 0388555 / 388555
• 0398385 / 398385
• 0395712 / 395712
• 0395718 / 395718
• 0383765 / 383765
• 0765591 / 765591
• 5005462
• Related pulse hose, fuel connectors and mounting gasket

Aftermarket / Verified Equivalents

• Recmar REC438559
• Peach Motor Parts PM-0438559
• Fuel Pump Factory replacement pump for 0438559
• OSFP559 aftermarket fuel pump
• Sierra 18-7351 and 18-7352 are catalogue-dependent functional alternatives for selected OMC pump configurations and should be matched by hose and pulse-port layout

📦 Condition

• Genuine used part
• Removed from running engine where applicable
• In good working condition unless otherwise stated