Fuel Pump Rebuild Kit for Mercury/Mariner 30–275 HP and Force 40–150 HP Outboards – Replaces 43990A10, 857005A1 and 18-7817
Fuel Pump Rebuild Kit for Mercury/Mariner 30–275 HP and Force 40–150 HP Outboards – Replaces 43990A10, 857005A1 and 18-7817 is backordered and will ship as soon as it is back in stock.
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Fuel Pump Rebuild Kit for Mercury/Mariner 30–275 HP and Force 40–15...
Fuel Pump Rebuild Kit for Mercury/Mariner 30–275 HP and Force 40–150 HP Outboards – Replaces 43990A10, 857005A1 and 18-7817 is backordered and will ship as soon as it is back in stock.
Product Details
This fuel pump rebuild kit is intended for compatible Mercury, Mariner and Force 2-stroke outboard fuel pump assemblies. It supplies replacement internal wear components for rebuilding an existing pump housing rather than replacing the complete fuel pump assembly.
The kit is listed as a replacement for several commonly referenced fuel pump numbers, including Mercury 43990A10 and 857005A1, Sierra 18-7817, and Red Rhino FM-803. Part-number references are provided for identification only. Confirm the number on your original pump and compare the component layout before ordering.
- Fuel pump repair/rebuild kit for compatible marine gasoline applications.
- Designed to replace internal service components in an existing pump housing.
- Includes diaphragms, gaskets, check-valve components and additional rebuild hardware as listed below.
- For 2-stroke outboard applications using a matching fuel pump design.
Part Number Matrix
The following numbers are reference numbers associated with this listing. They should not be treated as confirmation of fitment without matching the original pump, engine model and serial-number conditions.
| Brand | Reference Number |
|---|---|
| Mercury | 43990A10 |
| Mercury | 43990A11 |
| Mercury | 43990A7 |
| Mercury | 43990A9 |
| Mercury | 43990A4 |
| Mercury | 43990A8 |
| Mercury | 43990A6 |
| Mercury | 43990A1 |
| Mercury | 43990A5 |
| Mercury | 43990A3 |
| Mercury | 43990A2 |
| Sierra | 18-7817 |
| Red Rhino | FM-803 |
Engine and Model Compatibility
The listing is intended for compatible Mercury and Mariner 2-stroke outboards in the 30–275 HP range and compatible Force 2-stroke outboards in the 40–150 HP range. These horsepower ranges are not sufficient by themselves to establish fitment because fuel pump designs can vary by model, year, serial number and engine configuration.
| Brand | Listed Horsepower Range | Stroke | Fitment Condition |
|---|---|---|---|
| Mercury / Mariner | 30–275 HP | 2-Stroke | Must use a matching fuel pump assembly and reference number. |
| Force | 40–150 HP | 2-Stroke | Must use a matching fuel pump assembly and reference number. |
| Force | 50 HP | 2-Stroke | Listing notes specifically reference serial number OE065372 and later; verify the engine identification and original pump before ordering. |
Always verify the complete engine model, year, serial number, stroke type and number on the existing fuel pump. Do not rely on horsepower alone.
Technical Specifications
- Product Type
- Fuel pump repair/rebuild kit
- Application
- Compatible marine gasoline fuel pump assemblies
- Stroke
- 2-stroke applications as listed
- Fitment Type
- Vehicle-specific; verify the original pump and reference number
- Installation
- Rebuild of an existing fuel pump housing
- Connection
- For use with the existing fuel-line connections and matching pump housing
- Housing
- Existing metal pump housing is reused; a complete pump housing is not included
- Dimensions
- 107 × 83 × 18 mm (4.21 × 3.27 × 0.71 inches), listed package dimensions
- Weight
- 0.02 kg (0.634 oz), as listed
What's in the Box
- 1 × fuel pump rebuild kit
- Diaphragms
- Gaskets
- Check valves
- Spring
- Cap
- Screws
Package contents are intended for rebuilding the compatible existing pump. The complete metal fuel pump housing, engine and fuel lines are not included.
Installation Notes
- Confirm the engine and original pump reference number before beginning work.
- Work in a well-ventilated area away from flames, sparks and other ignition sources.
- Disconnect the battery and relieve fuel-system pressure where applicable.
- Label and disconnect the fuel lines, using suitable rags or containers to catch fuel.
- Remove the pump from the engine and note the orientation of the diaphragms, gaskets, valves, spring and cap.
- Disassemble the existing pump carefully and clean the reusable housing surfaces, removing old gasket material and debris.
- Install the rebuild components in the same order and orientation as the original parts.
- Reassemble the pump and reinstall it using the manufacturer's specified fastener torque.
- Reconnect the fuel lines, prime the system as required and check all connections.
- Start the engine only after confirming that there are no fuel leaks. Stop immediately if leakage or abnormal operation is observed.
Troubleshooting and FAQ
How do I know if my fuel pump may need rebuilding?
Possible symptoms include difficult starting, rough idling, engine bogging at higher speed, surging, loss of power or visible fuel leakage. These symptoms can also have other causes, so inspect the complete fuel system and follow the engine manufacturer's diagnostic procedures.
Will this kit fit my specific engine model and year?
Fitment cannot be confirmed from horsepower alone. Match the engine brand, model, year, serial number, stroke type and the number on the existing fuel pump. Compare the original component arrangement with the kit before installation.
Is this a complete fuel pump?
No. This is a rebuild kit for a compatible existing fuel pump. The metal housing and complete assembled pump are not included.
Does the kit include every component in the original pump?
The listed kit includes diaphragms, gaskets, check valves, a spring, a cap and screws. Reuse only housing components that are clean, undamaged and suitable for service. Replace a damaged housing or other non-included component as required.
Do I need special tools?
Basic hand tools are generally required, and a torque wrench is recommended for correct fastener tightening. Use appropriate fuel-system safety practices and consult the engine service manual for model-specific procedures.
Is this an OEM part?
This is an aftermarket rebuild kit. The reference numbers identify compatible or commonly compared applications and do not indicate that the kit is manufactured by Mercury, Mariner, Force or Sierra.
Safety and Important Information
- Verify the original pump number, engine model and serial number before ordering.
- Do not install the kit if the supplied components do not match the original pump layout.
- Use only with the fuel type and application specified for the engine.
- Inspect carefully for fuel leaks after installation and before normal operation.
- Professional installation is recommended when you are not familiar with marine fuel systems.
About Sea Sierra
- Marine Replacement Parts — Replacement components for maintaining compatible marine fuel and engine systems.
- Application-Focused Listings — Reference numbers and fitment information are provided to help compare the original component before ordering.
- Installation Awareness — Always follow the engine manufacturer's service instructions and applicable fuel-safety procedures.
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