Sierra 18-7843 6E5244110000Fuelpump Diaphrag
Sierra 18-7843 6E5244110000Fuelpump Diaphrag — Product description
Keeping your Yamaha outboard running smoothly starts with reliable fuel delivery, and the Sierra 18-7843 fuel pump diaphragm plays a crucial role in that process. This precision-engineered replacement part matches the original 6E5-24411-00-00 specifications, ensuring consistent fuel flow without the hassle of sourcing hard-to-find OEM components. Whether you're prepping for a weekend on the water or tackling a routine service, swapping in this diaphragm restores peak performance and prevents those frustrating stalls mid-trip.
Key Features and Why It Matters
- Durable Nitrile Construction: Built to resist the degrading effects of ethanol-blended fuels, which are notorious for cracking standard diaphragms over time. This material choice extends service life in harsh marine conditions.
- Exact OEM Fit: Designed as a drop-in replacement for Yamaha 115-130 HP 2-stroke models, eliminating guesswork and ensuring seamless integration with your existing fuel pump assembly.
- Enhanced Fuel Pulsation Control: Maintains steady pressure to your carburetors, reducing vapor lock risks during hot starts—a common headache in high-performance outboards.
- Lightweight and Responsive: Weighs just ounces but flexes reliably under vacuum, mimicking factory performance for optimal throttle response.
Boat owners rave about how this simple upgrade breathes new life into aging fuel systems, often cutting down on hard starts and improving overall efficiency without major overhauls.
Perfect Fit for Your Yamaha Outboard
This Sierra diaphragm slots right into fuel pumps on select Yamaha 2-stroke powerheads from the mid-80s through the 90s, including popular 115, 120, and 130 HP models in both enduro and standard configurations. Always cross-check your engine's serial number against the service manual to confirm compatibility, as variations exist across production runs. It's a staple for mechanics servicing offshore fishing rigs or family cruisers where reliability trumps all.
Step-by-Step Installation Tips
- Prep Work: Disconnect the fuel line and battery, then relieve system pressure by cracking the primer bulb.
- Disassemble Pump: Remove the cover screws, noting the orientation of the old diaphragm—mark if needed to avoid mix-ups.
- Replace and Inspect: Peel out the worn diaphragm, clean mating surfaces thoroughly, and press the new Sierra 18-7843 into place. Check the check valve and springs while you're in there.
- Reassemble and Test: Torque to spec (usually 20-30 in-lbs), reconnect everything, and run a pressure test with your fuel line tester before hitting the water.
- Pro Tip: Apply a dab of marine grease to the diaphragm edges for easier future access and to seal against leaks.
Most DIYers knock this out in under 30 minutes with basic tools—no special pullers required. If your pump body shows pitting from old fuel varnish, consider a full rebuild kit for longevity.
Maintenance and Common Issues to Watch
Fuel pump diaphragms wear from constant flexing and exposure to contaminants like water or dirt in your tank. Signs it's time for replacement include erratic idling, black smoke on acceleration, or fuel dribbling from the pump vent. Regular winterization with stabilizer helps, but inspect annually if you're running E10 or higher ethanol mixes.
Pair this diaphragm with fresh fuel lines and a quality inline filter to maximize uptime. In saltwater environments, rinse the exterior post-use to prevent corrosion from creeping into the pump internals.
Frequently Asked Questions
SKU: NVN-4003087
MPN: 18-7843
UPC: 808282260019
Technical specifications
| Brand | Sierra Engine Parts |
| Model | Sierra 18-7843 6E5244110000Fuelpump Diaphrag |
| SKU / MFR# | 4003087 |
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Frequently asked questions
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