Low Pressure Electric Fuel Pump – Fits MerCruiser 4.3L, 5.0L, 5.7L (Replaces 861155A3)
Low Pressure Electric Fuel Pump – Fits MerCruiser 4.3L, 5.0L, 5.7L (Replaces 861155A3) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
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Low Pressure Electric Fuel Pump – Fits MerCruiser 4.3L, 5.0L, 5.7L (Replaces 861155A3) is backordered and will ship as soon as it is back in stock.
Product Details
This Low Pressure Electric Fuel Pump is a direct-fit replacement for carbureted MerCruiser 4.3L V6, 5.0L V8, and 5.7L V8 engines from model year 1998 and newer. It is engineered to restore original fuel system performance and reliability, ensuring your engine receives a consistent fuel supply at the correct pressure.
Serves as a direct interchange for Mercury MerCruiser part numbers 861155004, 861155A2, 861155A3, and 861155A6, as well as aftermarket references Sierra 18-8867, EMP 1397-97000, and YOHIB OEN 861155A3.
- Designed for simple inline installation.
- Compatible with gasoline fuel systems (not for fuel-injected engines).
- Includes a pre-installed multi-pin electrical connector for plug-and-play setup.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury MerCruiser | 861155004 |
| Mercury MerCruiser | 861155A2 |
| Mercury MerCruiser | 861155A3 |
| Mercury MerCruiser | 861155A6 |
| Sierra | 18-8867 |
| EMP | 1397-97000 |
| YOHIB | OEN 861155A3 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For MerCruiser models, this pump is specifically for carbureted V6 and V8 engines (Gen+) manufactured in 1998 or later. It is not compatible with EFI, MPI, or other fuel-injected systems.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| MerCruiser | 4.3L Alpha/Bravo (262 CID - Gen+) | 4.3L V6 | 4-Stroke | 1998 and up | 861155A3 | For carbureted engines only |
| MerCruiser | 4.3LH (Gen+) (4 BBL.) GM 262 V-6 | 4.3L V6 | 4-Stroke | 1998 and up | 861155A3 | For carbureted engines only |
| MerCruiser | 4.3L CARB ALPHA/BRAVO | 4.3L V6 | 4-Stroke | 1998 and up | 861155A3 | For carbureted engines only |
| MerCruiser | 4.3L Alpha 4V | 4.3L V6 | 4-Stroke | 1998 and up | 861155A3 | For carbureted engines only |
| MerCruiser | 5.0L Alpha/Bravo Gen+ | 5.0L V8 | 4-Stroke | 1998–2001 | 861155A3 | For carbureted engines only |
| MerCruiser | 5.0L (2 BBL.) GM 305 V-8 | 5.0L V8 | 4-Stroke | 1998–2001 | 861155A3 | For carbureted engines only |
| MerCruiser | 5.7L Alpha/Bravo Gen+ | 5.7L V8 | 4-Stroke | 1998–2001 | 861155A3 | For carbureted engines only |
| MerCruiser | 5.7L CARB ALPHA/BRAVO | 5.7L V8 | 4-Stroke | 1998 and up | 861155A3 | For carbureted engines only |
| MerCruiser | 5.7L CARB (MIE) (GEN+) | 5.7L V8 | 4-Stroke | 1998 and up | 861155A3 | For carbureted engines only |
| MerCruiser | 5.7L CARB INBOARD | 5.7L V8 | 4-Stroke | 1998 and up | 861155A3 | For carbureted engines only |
| MerCruiser | 5.7L CARB MIE | 5.7L V8 | 4-Stroke | 1998 and up | 861155A3 | For carbureted engines only |
| MerCruiser | 5.7L CARB SKI | 5.7L V8 | 4-Stroke | 1998 and up | 861155A3 | For carbureted engines only |
| MerCruiser | 5.7L COMPETITION SKI ENGINE (GEN+) | 5.7L V8 | 4-Stroke | 1998 and up | 861155A3 | For carbureted engines only |
| MerCruiser | 350 MAG MPI SKI | 5.7L V8 | 4-Stroke | 1998 and up | 861155A3 | For carbureted engines only |
| MerCruiser | 383 MAG STROKER | 6.3L V8 | 4-Stroke | 1998 and up | 861155A3 | For carbureted engines only |
Technical Specs
- Product Type
- Low Pressure Electric Fuel Pump
- Installation
- Inline
- Fuel Type
- Gasoline (not for fuel injected engines)
- Connection
- Multi-pin electrical connector
- Housing Material
- Aluminum
- Housing Color
- Silver/Natural
- Dimensions
- 22.0 × 14.0 × 8.5 cm
- Weight
- 0.671 kg (1.48 lb)
- Fitting Type
- Threaded inlet and outlet
- Working Pressure
- 8-10 PSI
- Voltage
- 12V DC
What’s in the Box
- 1 x Fuel Pump Electric (861155A3)
- 1 x Lead Wires with Multi-pin Connector
- 1 x Fittings (805027)
- 1 x O-Ring (0.530 x 0.082 in) (805062)
- 1 x O-Ring (0.301 x 0.070 in) (805063)
Installation Notes
- Disconnect the boat's battery.
- Safely relieve any pressure from the fuel system. Place absorbent rags under the fuel line connections.
- Carefully disconnect the fuel lines from the old pump. Note the inlet and outlet orientation.
- Unplug the electrical connector and unbolt the old pump from its mounting location.
- Install the new fuel pump, ensuring it is securely mounted.
- Connect the fuel lines to the new pump using the supplied fittings and O-rings. Ensure connections are tight to prevent leaks.
- Plug in the new electrical connector.
- Reconnect the battery.
- Turn the ignition key to the "On" position several times (without starting the engine) to prime the system.
- Thoroughly inspect all connections for any signs of fuel leaks before starting the engine.
Troubleshooting & FAQ
How do I confirm if this pump fits my engine?
Verify your complete engine model, serial number range, and year against the compatibility chart in this listing. This pump is only for carbureted MerCruiser 4.3L, 5.0L, and 5.7L engines from 1998 and later. Do not rely on visual comparison alone.
Is this pump for fuel-injected (EFI/MPI) engines?
No. This is a low-pressure pump designed exclusively for carbureted engines, operating at 8-10 PSI. Fuel-injected systems require high-pressure pumps and will not function with this part.
What are common signs of a failing fuel pump?
Symptoms include difficulty starting, engine sputtering or stalling (especially under load or at high speeds), loss of power, and unusual whining noises from the fuel tank area. A fuel pressure test is the most reliable diagnostic method.
What makes this different from the OEM MerCruiser pump?
Functionally, it is a direct replacement designed to meet or exceed original specifications for pressure, flow, and fit. The primary difference is that it is an aftermarket part, offering a better value without sacrificing quality.
Is any special maintenance required?
No specific maintenance is required for the pump itself. However, to ensure its longevity, it's critical to maintain a clean fuel system. Regularly replace your boat's fuel filter(s) according to the manufacturer's service schedule.
OEM vs. Aftermarket?
This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.
Shipping speed & cost?
We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.
Warranty & returns?
Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.
Safety & Important Info
- Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
- This is an aftermarket replacement, not an OEM component.
- Professional installation is recommended for safety and performance.
About Sea Sierra
- Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
- Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
- Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.
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