Fuel Pump – Fits Mercury/Mariner 4-Stroke 4-6HP (Replaces 803529T06, 803529T01, 803529T02, 803529T03, 3H6-04000-7)
Fuel Pump – Fits Mercury/Mariner 4-Stroke 4-6HP (Replaces 803529T06, 803529T01, 803529T02, 803529T03, 3H6-04000-7) is backordered and will ship as soon as it is back in stock.
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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 – Fits Mercury/Mariner 4-Stroke 4-6HP (Replaces 803529T06...
Product Details
This is a replacement Fuel Pump that fits Mercury/Mariner 4-Stroke 4HP, 5HP, and 6HP outboard engines. It is engineered to meet or exceed original equipment specifications, ensuring reliable fuel delivery for your marine engine.
It serves as a direct interchange for Mercury/Mariner part numbers 803529T06, 803529T01, 803529T02, 803529T03, and Tohatsu part number 3H6-04000-7.
- Designed for direct OEM replacement fit and function.
- Constructed from a durable blend of plastic and metal.
- Mechanically operated for consistent performance.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury/Mariner | 803529T06 |
| Mercury/Mariner | 803529T01 |
| Mercury/Mariner | 803529T02 |
| Mercury/Mariner | 803529T03 |
| Tohatsu | 3H6-04000-7 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This fuel pump is confirmed to fit the specified horsepower ranges for Mercury, Mariner, and Tohatsu 4-stroke outboards.
| Brand | Rated HP | Stroke | OEM Part No. |
|---|---|---|---|
| Mercury | 4 HP | 4-Stroke | 803529T06, 803529T01, 803529T02, 803529T03 |
| Mercury | 5 HP | 4-Stroke | 803529T06, 803529T01, 803529T02, 803529T03 |
| Mercury | 6 HP | 4-Stroke | 803529T06, 803529T01, 803529T02, 803529T03 |
| Mariner | 4 HP | 4-Stroke | 803529T06, 803529T01, 803529T02, 803529T03 |
| Mariner | 5 HP | 4-Stroke | 803529T06, 803529T01, 803529T02, 803529T03 |
| Mariner | 6 HP | 4-Stroke | 803529T06, 803529T01, 803529T02, 803529T03 |
| Tohatsu | 4 HP | 4-Stroke | 3H6-04000-7 |
| Tohatsu | 5 HP | 4-Stroke | 3H6-04000-7 |
| Tohatsu | 6 HP | 4-Stroke | 3H6-04000-7 |
Technical Specs
- Product Type
- Mechanical Fuel Pump
- Installation
- Direct OEM Replacement
- Fuel Type
- Gasoline
- Connection
- Hose Barb
- Housing Material
- Plastic, Metal
- Housing Color
- Black
- Fitting Type
- Vehicle Specific Fit
- Warranty
- Varies by seller (typically 30-day return, 6-month warranty)
- Other Technical Attributes
- Mechanical operation
What's in the Box
- 1 x Fuel Pump (Replaces 803529T06/803529T01/803529T02/803529T03)
Installation Notes
- Ensure the engine is off and cool. Disconnect the negative battery terminal for safety.
- Carefully relieve any pressure from the fuel system. Place rags around the fuel lines to catch any spillage.
- Note the orientation of the fuel lines, then disconnect them from the old pump.
- Unbolt and remove the old fuel pump from the engine block.
- Clean the mounting surface to ensure a good seal.
- Install the new fuel pump, ensuring it is correctly seated. Tighten mounting bolts to the manufacturer's specified torque.
- Reconnect the fuel lines to the correct ports on the new pump and secure any clamps.
- Reconnect the battery terminal, prime the fuel system if necessary, and check for leaks before starting the engine.
Troubleshooting & FAQ
How do I confirm this fits my specific engine model and year?
The best method is to match your old part number to one of the numbers listed in our Part Number Matrix (803529T06, 803529T01, etc.). While this pump fits the general 4-6HP range for Mercury/Mariner 4-strokes, checking the part number is the most accurate way to guarantee compatibility.
What are common signs of a failing fuel pump?
Symptoms include the engine sputtering or losing power at high speeds, difficulty starting, stalling, or a noticeable decrease in overall performance. A physical inspection might reveal cracks or leaks on the pump housing.
Is any maintenance required for this fuel pump?
This mechanical pump is designed to be maintenance-free. However, ensuring your fuel tank is clean and using a quality fuel filter can prolong its service life by preventing debris from entering the pump.
Is this an OEM part?
This is an aftermarket replacement part, not an OEM component. It is manufactured in an ISO 9002 certified facility to meet or exceed original equipment specifications for fit, form, and function, providing a reliable alternative to dealer parts.
What are your shipping speeds and costs?
We ship worldwide. Standard shipping is typically free, with most orders arriving within 5 to 15 business days. Expedited shipping options, if available for your location, will be presented at checkout.
What is the warranty and return policy?
This product is covered by a 1-year warranty against manufacturing defects under normal use. If you encounter an issue, please contact our support team with your order number. We accept returns on unused items in their original condition within our standard return window.
Safety & Important Info
- Verify images and specifications against 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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