Diaphragm Kit – Fits Mercury/Mariner 200 hp (Replaces Mercury/Mariner/Force 89031A4)
Diaphragm Kit – Fits Mercury/Mariner 200 hp (Replaces Mercury/Mariner/Force 89031A4) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Diaphragm Kit – Fits Mercury/Mariner 200 hp (Replaces Mercury/Marin...
Product Details
This Diaphragm Kit is designed for use in the fuel pumps of specific Mercury/Mercruiser engines, including Mercury/Mariner 200 hp models from 1978–1988. It serves as a crucial component for restoring fuel system performance and reliability.
This kit provides a direct interchange for Mercury/Mariner/Force part number 89031A4, EMP 1399-00087, and GLM Marine 40380.
- Installs within the fuel pump assembly.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury/Mariner/Force | 89031A4 |
| EMP | 1399-00087 |
| GLM Marine | 40380 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
Compatibility for Mercury/Mariner models:
| Brand | Model | Rated HP | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|
| Mercury/Mariner | V-200 | 200 | 1978–1988 | 89031A4 | Fuel Pump (Design II) |
| Mercury/Mariner | V-200 | 200 | 5624878 THRU 0C100860 | 89031A4 | Fuel Pump (Design II) |
Technical Specs
- Product Type
- Diaphragm Kit
- Installation
- Fuel Pump
- Dimensions
- Height: 6.0 in; Width: 7.5 in; Length: 1.5 in
- Weight
- 0.027 kg (0.06 lbs)
What’s in the Box
- Diaphragm (Replaces OEM 89031A4)
Installation Notes
- Disconnect the negative battery terminal to prevent electrical shorts.
- Safely relieve pressure from the fuel system according to your engine's service manual.
- Carefully disconnect the fuel inlet and outlet lines from the fuel pump. Have rags ready to catch any residual fuel.
- Remove the mounting bolts securing the fuel pump to the engine block and detach the pump.
- Disassemble the fuel pump housing to access the old diaphragm. Note the orientation of all components.
- Remove the old diaphragm and inspect the housing for debris or wear.
- Install the new diaphragm, making sure it is properly seated and aligned.
- Reassemble the fuel pump, torquing screws to the manufacturer's specification.
- Reinstall the pump onto the engine, reconnect fuel lines, and secure the battery terminal.
- Prime the fuel system and check thoroughly for leaks before starting the engine.
Troubleshooting & FAQ
How do I verify this kit fits my engine?
Check the Engine & Model Compatibility table. It’s critical to match your engine's model, HP, and year/serial range. Cross-reference the OEM part number 89031A4 with your engine’s service manual to ensure a correct match.
What are common symptoms of a bad fuel pump diaphragm?
Signs include engine hesitation, sputtering, poor acceleration, difficulty starting, or visible fuel leaks around the pump. A ruptured diaphragm can also allow fuel to enter the crankcase, contaminating the oil.
How often should the fuel pump diaphragm be replaced?
Replacement intervals vary based on usage, fuel type, and age. It is recommended to inspect the diaphragm during routine service and replace it preventatively every few seasons or immediately if you notice any performance issues or signs of wear.
Is installation difficult?
Installation requires mechanical experience, including safely relieving fuel pressure and handling fuel system components. For safety and reliability, professional installation is strongly recommended.
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.
Payment & Security
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