Fuel Pump Base Gasket – Fits Mercury Marine 40-250 HP Outboards (Replaces 27-987691, 27-98769)
Fuel Pump Base Gasket – Fits Mercury Marine 40-250 HP Outboards (Replaces 27-987691, 27-98769) is backordered and will ship as soon as it is back in stock.
Couldn't load pickup availability
Worry-free returns
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.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.
Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Fuel Pump Base Gasket – Fits Mercury Marine 40-250 HP Outboards (Re...
Product Details
This high-quality aftermarket Fuel Pump Base Gasket – Fits Mercury Marine 40-250 HP Outboards (Replaces 27-987691, 27-98769) provides a reliable seal between the fuel pump and engine block. It is designed for a wide range of Mercury Marine 2-stroke and 4-stroke outboard engines, from 40 HP to 250 HP, ensuring a precise fit for preventing fuel leaks.
It serves as a direct replacement for Mercury Marine part numbers 27-98769, 27-987691, and 8M0204705, as well as aftermarket equivalents from Sierra Marine (18-0970-9), Mallory (9-60054), and GLM (32960).
- Ensures a secure, leak-free seal between the fuel pump and engine.
- Direct replacement design for straightforward installation.
- Covered by a limited lifetime warranty from Sierra Marine.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number | Superseded By |
|---|---|---|
| Mercury Marine | 27-98769 | 8M0204705 |
| Mercury Marine | 27-987691 | 8M0204705 |
| Mercury Marine | 8M0204705 | |
| Sierra Marine | 18-0970-9 | |
| Mallory | 9-60054 | |
| GLM | 32960 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This gasket fits a wide variety of Mercury Marine outboards. Please check your specific model and OEM part number against this table.
| Model | Rated HP | Stroke / Cylinder | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|
| Outboard 30-40 Jet | 30-40 | 2-Stroke | Various | 27-987691 | Superseded by 8M0204705 |
| Outboard 30-40 | 30-40 | 2-Stroke | Various | 27-987691 | Superseded by 8M0204705 |
| Outboard 45-65 Jet | 45-65 | 2-Stroke | Various | 27-987691 | Superseded by 8M0204705 |
| Outboard 45-60 | 45-60 | 2-Stroke | Various | 27-987691 | Superseded by 8M0204705 |
| Outboard 70-90 | 70-90 | 3 Cylinder | Various | 27-987691 | Superseded by 8M0204705 |
| Outboard 75-125 | 75-125 | 3-4 Cylinder | Various | 27-987691 | Superseded by 8M0204705 |
| Outboard 100-115 | 100-115 | 4-6 Cylinder | Various | 27-987691 | Superseded by 8M0204705 |
| Outboard 150-250 | 150-250 | Various | Various | 27-987691 | Superseded by 8M0204705 |
| DFI 2.5L & 3.0L Models | 90-250 | Various | Various | 27-987691 | Superseded by 8M0204705 |
| Sport Jet 175XR2 | 175 | Various | Various | 27-987691 | Superseded by 8M0204705 |
| Sport Jet 210/240 | 210-240 | Various | Various | 27-987691 | Superseded by 8M0204705 |
Technical Specs
- Product Type
- Fuel Pump Base Gasket
- Installation
- Direct replacement
- Fuel Type
- Gasoline
- Housing Material
- Gasket material (unspecified)
- Dimensions
- 1.13" L x 5.13" W x 4.0" H
- Warranty
- Sierra Marine: Limited lifetime warranty
- Other Technical Attributes
- Used to seal between fuel pump and engine block
What’s in the Box
- 2 x Gasket Base (Replaces 27-987691/8M0204705)
Installation Notes
- Disconnect the battery and relieve any pressure from the fuel system.
- Carefully disconnect the fuel lines and remove the bolts securing the fuel pump.
- Remove the old fuel pump and gasket. Thoroughly clean the mounting surfaces on the engine block and pump, removing all old gasket material and residue.
- Position the new gasket on the engine block, aligning it with the mounting holes.
- Install the fuel pump over the new gasket and tighten the bolts to the manufacturer's specified torque.
- Reconnect the fuel lines securely.
- Reconnect the battery, prime the fuel system, and check for any leaks around the gasket and fuel line connections before starting the engine.
Troubleshooting & FAQ
How do I know if this gasket will fit my specific engine?
The best way to ensure compatibility is to verify your engine's model and year against the "Engine & Model Compatibility" table. Cross-reference the OEM part number (27-98769 or 27-987691) with your engine's service manual or existing part.
What are the signs of a failing fuel pump gasket?
Common symptoms include visible fuel leakage around the fuel pump base, a strong smell of gasoline, poor engine performance, hesitation during acceleration, or difficulty starting the engine due to a loss of fuel pressure.
Is this a single gasket or a multipack?
This package includes a set of two gaskets, providing a spare or allowing for replacement on twin-engine setups.
Do I need to use a sealant with this gasket?
Generally, these gaskets are designed to be installed dry. However, always consult your engine's service manual for specific recommendations. In some cases, a light, non-hardening sealant may be advised.
When should this gasket be replaced?
The gasket should be replaced any time the fuel pump is removed for service or replacement. It should also be replaced immediately if there are any signs of leakage or damage.
What is the gasket made of?
While the exact composition is proprietary, it is made from a high-quality, durable gasket material specifically designed to withstand gasoline and engine bay conditions, ensuring a long-lasting seal.
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
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
