Thermostat Gasket – Fits Yamaha 75-225 HP Outboard Motors (Replaces 688-12414-A1-00, 688-12414-00-00)
Thermostat Gasket – Fits Yamaha 75-225 HP Outboard Motors (Replaces 688-12414-A1-00, 688-12414-00-00) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
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Thermostat Gasket – Fits Yamaha 75-225 HP Outboard Motors (Replaces...
Thermostat Gasket – Fits Yamaha 75-225 HP Outboard Motors (Replaces 688-12414-A1-00, 688-12414-00-00) is backordered and will ship as soon as it is back in stock.
Product Details
This Thermostat Gasket – Fits Yamaha 75-225 HP Outboard Motors (Replaces 688-12414-A1-00, 688-12414-00-00) is designed for a wide range of Yamaha 2-Stroke V4 and V6 outboard engines, including models from 75 HP to 225 HP manufactured from 1992 and later. It ensures a reliable seal for the thermostat housing, which is critical for maintaining proper engine operating temperature.
This part is a direct replacement for Yamaha OEM part numbers 688-12414-A1-00, 688-12414-A0-00, and 688-12414-00-00. It also interchanges with Sierra 18-0844 and Mallory 9-60003.
- Engineered for direct-fit installation.
- Made from high-temperature resistant material for durability.
- Seals the thermostat cover to prevent coolant leaks.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Yamaha | 688-12414-A1-00 |
| Yamaha | 688-12414-A0-00 |
| Yamaha | 688-12414-00-00 |
| Sierra | 18-0844 |
| Mallory | 9-60003 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
This gasket is confirmed to fit the following Yamaha outboard models.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. |
|---|---|---|---|---|---|
| Yamaha | 75A | 75 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | E75B | 75 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 75C | 75 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | P75 | 75 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 80A | 80 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 85A | 85 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 90E | 90 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 90A | 90 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | B90 | 90 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | C90 | 90 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 100A | 100 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 115E | 115 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 115A | 115 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | E115A | 115 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 115B | 115 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 115C | 115 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | B115 | 115 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | S115 | 115 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 130B | 130 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | S130 | 130 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 140A | 140 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 140B | 140 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 150E | 150 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 150A | 150 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 150C | 150 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 150F | 150 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 150G | 150 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | D150H | 150 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 150J | 150 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 150L | 150 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | D150N | 150 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | Z150P | 150 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | Z150Q | 150 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | S150 | 150 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | SX150 | 150 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | V150 | 150 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | VX150 | 150 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | ProV150 | 150 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 175A | 175 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 175B | 175 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 175D | 175 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 175F | 175 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | Z175G | 175 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | Z175H | 175 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | S175 | 175 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | V175 | 175 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | VZ175 | 175 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 200E | 200 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 200A | 200 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 200B | 200 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 200C | 200 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | Pro V 200 | 200 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 200F | 200 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 200G | 200 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 200J | 200 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | Z200N | 200 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | Z200P | 200 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | S200 | 200 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | SX200 | 200 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | VZ200 (2.6L) | 200 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | Z200 (2.6L) | 200 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 220A | 220 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 225A | 225 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 225B | 225 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
| Yamaha | 225D | 225 | 2-Stroke | 1992 and later | 688-12414-A1-00 |
Technical Specs
- Product Type
- Thermostat Cover Gasket
- Fitment
- Yamaha V4, V6 2-Stroke Outboards
- Material
- High-temperature resistant material
- Shape
- Rectangular
- Installation
- Direct replacement
- Weight
- 0.63 oz (17.9 g)
- Warranty
- 30-day return/replacement (Amazon)
What’s in the Box
- 1 x Thermostat Gasket (688-12414-A1-00)
Installation Notes
- Ensure the engine is off and cool. Disconnect the negative battery terminal for safety.
- Locate the thermostat housing on the engine block. Place a drain pan beneath it.
- Carefully remove the bolts securing the thermostat cover. Note their lengths and positions.
- Gently pry the cover off. If it is stuck, tap it lightly with a rubber mallet. Do not force it.
- Remove the old gasket and any remaining sealant or residue from both the cover and the engine block surfaces.
- Place the new gasket onto the clean surface of the engine block, ensuring it aligns with the bolt holes.
- Reinstall the thermostat cover and tighten the bolts in a crisscross pattern to the manufacturer-specified torque.
- Reconnect the battery terminal, refill any lost coolant, and check for leaks after starting the engine.
Troubleshooting & FAQ
How do I know if my thermostat gasket is failing?
Signs of a failing thermostat gasket include visible coolant leaks around the thermostat housing, engine overheating, or fluctuating temperature gauge readings. A physical inspection may reveal a cracked, brittle, or compressed gasket.
Is this gasket compatible with V-MAX or HPDI models?
This gasket fits a broad range of Yamaha V4 and V6 2-stroke engines, which includes many standard, V-MAX, and HPDI models between 75-225 HP from 1992 onward. Always verify your specific OEM part number (688-12414-A1-00) and engine model from our compatibility table before purchasing.
What is the recommended replacement interval?
There is no fixed replacement interval for a thermostat gasket. It should be replaced whenever the thermostat is serviced or if you notice any signs of a leak or engine cooling problems. It is good practice to replace it as a preventative measure during major engine services.
Can I reuse my old gasket?
No. Gaskets are single-use components designed to compress and create a seal. Reusing an old gasket will likely result in an improper seal and lead to coolant leaks.
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.
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