Fuel Connector Cap – Fits Mercury 4–30 HP (Replaces Mercury 878311, Suzuki 65727-91JL0, Tohatsu 3H6-70262-0)
Fuel Connector Cap – Fits Mercury 4–30 HP (Replaces Mercury 878311, Suzuki 65727-91JL0, Tohatsu 3H6-70262-0) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
Orders are typically processed within 1–2 business days.
U.S. orders usually arrive within 6–15 days, depending on stock location and destination.
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Fuel Connector Cap – Fits Mercury 4–30 HP (Replaces Mercury 878311,...
Fuel Connector Cap – Fits Mercury 4–30 HP (Replaces Mercury 878311, Suzuki 65727-91JL0, Tohatsu 3H6-70262-0) is backordered and will ship as soon as it is back in stock.
Product Details
This Fuel Connector Cap is designed to seal the fuel connection on integral fuel tanks used with selected Mercury outboard engines. It is intended for various Mercury models from 4 HP to 30 HP, primarily four-stroke applications.
This aftermarket replacement is listed for Mercury 878311, QuickSilver 878311, Suzuki 65727-91JL0, and Tohatsu 3H6-70262-0 applications.
- Hand-installed screw-on design.
- Designed for gasoline-fueled integral, or built-in, fuel tanks.
- Package includes one fuel connector cap.
Part Number Matrix
Use the following references to compare the replacement cap with the part removed from your engine.
| Brand | Part Number | Notes |
|---|---|---|
| Mercury | 878311 | Listed replacement reference |
| QuickSilver | 878311 | Listed replacement reference |
| Suzuki | 65727-91JL0 | Listed cross-reference |
| Tohatsu | 3H6-70262-0 | Listed cross-reference |
Engine & Model Compatibility
Compatibility information below is representative rather than an exhaustive model list. Confirm the engine model, fuel-tank arrangement, and part number before ordering.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Mercury | Multiple | 4 | 4-Stroke | Not specified | 878311 | For compatible integral fuel-tank applications |
| Mercury | Multiple | 5 | 4-Stroke | Not specified | 878311 | For compatible integral fuel-tank applications |
| Mercury | Multiple | 6 | 4-Stroke | Not specified | 878311 | For compatible integral fuel-tank applications |
| Mercury | Multiple | 8 | 4-Stroke | Not specified | 878311 | For compatible integral fuel-tank applications |
| Mercury | Multiple | 9.9 | 4-Stroke | Not specified | 878311 | For compatible integral fuel-tank applications |
| Mercury | Multiple | 10 | 4-Stroke | Not specified | 878311 | For compatible integral fuel-tank applications |
| Mercury | Multiple | 15 | 4-Stroke | Not specified | 878311 | For compatible integral fuel-tank applications |
| Mercury | Multiple | 20 | 4-Stroke | Not specified | 878311 | For compatible integral fuel-tank applications |
| Mercury | Multiple | 25 | 4-Stroke | Not specified | 878311 | For compatible integral fuel-tank applications |
| Mercury | Multiple | 30 | 4-Stroke | Not specified | 878311 | For compatible integral fuel-tank applications |
Technical Specs
- Product Type
- Fuel connector cap
- Installation
- Screw-on, hand-tightened
- Fuel Type
- Gasoline
- Connection
- Integral fuel-tank inlet
- Housing Material
- Rubber
- Housing Color
- Black
- Application
- Compatible integral, or built-in, fuel tanks
What’s in the Box
- 1 x fuel connector cap
Installation Notes
- Make sure the engine is switched off and work in a well-ventilated area.
- Carefully unscrew the old fuel cap to release any built-up pressure.
- Remove the old cap and inspect the tank sealing surface for dirt, wear, or damage.
- Clean the inlet threads and sealing surface with a lint-free cloth.
- Position the replacement cap and screw it on by hand until snug. Do not overtighten.
- Before operating the engine, check the cap area for fuel odor or leakage.
Troubleshooting & FAQ
Does this cap fit all Mercury 4–30 HP models?
No fitment statement should be treated as universal. This cap is intended for selected Mercury four-stroke outboards from 4 HP to 30 HP that use a compatible integral fuel tank. Verify the original part number, tank arrangement, and physical connection before ordering.
What are the signs that the fuel connector cap needs replacement?
Common signs include cracks, brittleness, a loose or improper fit, a persistent fuel smell, or fuel leakage around the cap. A worn seal can compromise the fuel connection.
Is this a genuine OEM part?
No. This listing is for an aftermarket replacement designed for applications associated with Mercury 878311, Suzuki 65727-91JL0, Tohatsu 3H6-70262-0, and QuickSilver 878311.
Can this cap be used with diesel or another fuel type?
This cap is intended for gasoline-fueled outboard applications. Do not use it with another fuel type unless compatibility has been confirmed by the engine or fuel-system manufacturer.
How do I ensure a proper seal?
Clean the threads and sealing surface, then hand-tighten the cap until snug. Overtightening may damage the threads or seal. Check for gaps, fuel odor, and leakage before use.
My engine model is not listed, but the part number matches. Will it fit?
A matching reference number is a useful compatibility indicator, but it does not replace checking the tank design and connection. Confirm that your original cap corresponds to one of the listed references and that the replacement matches in shape and attachment method.
What is the difference between OEM and aftermarket?
This is an aftermarket replacement, not a genuine OEM component. Compare the replacement with the original part and verify compatibility before installation.
Shipping speed and cost
Typical transit is 5–15 days. Standard shipping is free, and expedited options may be available at checkout depending on destination.
Warranty and returns
This product is covered by the applicable warranty and return terms shown by the seller. Contact support with your order details if you receive a damaged or defective item.
Safety & Important Information
- Verify the original part, connection, and fuel-tank arrangement before purchase.
- This is an aftermarket replacement, not an OEM component.
- Stop using the engine if fuel leakage or a persistent fuel odor is present.
- Professional installation is recommended when the fuel connection or sealing surface is damaged.
About Sea Sierra
- Pro-Grade Standards — Marine replacement parts selected for dependable real-world service.
- Fast Global Fulfillment — Free standard delivery to most regions, with typical transit of 5–15 days.
- Manufacturer-Direct Value — Practical replacement solutions with attention to materials and quality control.
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