V-Belt – Fits MerCruiser 120-140HP, 2.5L-3.0L (Replaces 57-65607Q)
V-Belt – Fits MerCruiser 120-140HP, 2.5L-3.0L (Replaces 57-65607Q) is backordered and will ship as soon as it is back in stock.
Worry-free returns
Worry-free returns
Shop with confidence. If you’re not completely satisfied, eligible items may be returned within the return window, provided they are unused and in original packaging.
If the return is due to our error or a defective item, we’ll make it right.
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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.
International delivery times may vary due to customs processing.
Tracking information will be provided once your order ships.
V-Belt – Fits MerCruiser 120-140HP, 2.5L-3.0L (Replaces 57-65607Q)
V-Belt – Fits MerCruiser 120-140HP, 2.5L-3.0L (Replaces 57-65607Q) is backordered and will ship as soon as it is back in stock.
Product Details
This high-quality V-Belt – Fits MerCruiser 120, 140, 2.5L, 3.0L Engines is designed for the power steering system on various stern drive models manufactured between 1974 and 2008. It serves as a reliable replacement to restore proper power steering function and performance.
This belt is a direct replacement for Mercury/MerCruiser part numbers 57-65607Q, 57-65607, and 57-65607T. It also interchanges with aftermarket references such as Sierra 18-15370 and FridayParts 18-15370.
- Designed specifically for power steering pump applications on listed models.
- Constructed from a durable rubber and fiber composite for longevity and grip.
- Total length of 37 inches (940 mm) provides a precise fit for correct tension.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket brands.
| Brand | Part Number |
|---|---|
| Mercury/MerCruiser | 57-65607Q |
| Mercury/MerCruiser | 57-65607 |
| Mercury/MerCruiser | 57-65607T |
| Sierra | 18-15370 |
| FridayParts | 18-15370 |
Engine & Model Compatibility
Confirm your engine model and year in the table below to ensure correct fitment.
This power steering belt is engineered for the following MerCruiser (Mercury Marine) engines.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| MerCruiser | 120 | 120 | 4-Stroke | 1974–1982 | 57-65607Q | 153 CID / L4 engines |
| MerCruiser | 120 | 120 | 4-Stroke | 1982–1986 | 57-65607Q | 153 CID / L4 engines |
| MerCruiser | 2.5L | 120 | 4-Stroke | 1987–1989 | 57-65607Q | 153 CID / L4 engines |
| MerCruiser | 140 | 140 | 4-Stroke | 1974–1982 | 57-65607Q | 181 CID / L4 engines |
| MerCruiser | 140 | 140 | 4-Stroke | 1982–1999 | 57-65607Q | 181 CID / L4 engines |
| MerCruiser | 3.0L | 140 | 4-Stroke | 1987–1994 | 57-65607Q | 181 CID / L4 engines |
| MerCruiser | 3.0L | 140 | 4-Stroke | 1998–1999 | 57-65607Q | 181 CID / L4 engines |
| MerCruiser | 3.0L | 140 | 4-Stroke | 1999–2008 | 57-65607Q | 181 CID / L4 engines |
| MerCruiser | 3.0LX | 140 | 4-Stroke | 1990–1995 | 57-65607Q | 181 CID / L4 engines |
| MerCruiser | 3.0LX | 140 | 4-Stroke | 1986–1997 | 57-65607Q | 181 CID / L4 engines |
Technical Specs
- Product Type
- V-Belt
- Installation
- Power Steering Belt
- Housing Material
- Rubber/Fiber Composite
- Housing Color
- Black
- Dimensions
- 37 inches (940 mm)
- Fitting Type
- Standard V-Belt
What’s in the Box
- 1 x V-Belt (57-65607Q)
Installation Notes
- Disconnect the boat's battery cables for safety.
- Locate the power steering pump and note the routing of the existing belt. Taking a photo can be helpful.
- Loosen the tensioner pulley or the pump's mounting bolts just enough to release tension on the belt.
- Carefully slip the old belt off the pulleys.
- Compare the new belt against the old one to confirm the length and width are identical.
- Route the new belt correctly around the crankshaft, power steering pump, and any idler pulleys.
- Re-apply tension to the belt. As a general guide, there should be about a half-inch of deflection when pressed firmly. Do not overtighten, as this can damage bearings.
- Tighten all mounting and tensioner bolts to the manufacturer's specified torque.
- Reconnect the battery, start the engine, and verify the belt runs smoothly without squealing or wobbling.
Troubleshooting & FAQ
How do I know if this belt is correct for my engine?
This belt fits MerCruiser 120 HP, 140 HP, 2.5L, and 3.0L 4-cylinder engines from 1974–2008 for power steering applications. To guarantee fitment, please verify your engine model and year against our detailed compatibility table.
Is this belt for the alternator or power steering pump?
This is the power steering belt. Your engine may require a different belt part number for the alternator or raw water pump. Always confirm the specific application before ordering.
What are the signs of a failing V-belt?
Common symptoms include a high-pitched squeal from the engine bay, visible cracks or fraying on the belt's surface, glazing (shiny sides), or a noticeable decrease in power steering assistance, especially at low speeds.
How often should I replace my power steering belt?
There is no strict replacement interval. We recommend inspecting all belts during routine engine service (e.g., every 50-100 hours). Replace the belt immediately if you notice any signs of wear, damage, or stretching to avoid unexpected failure.
What is the difference between an OEM and an aftermarket part?
This listing is for an aftermarket replacement, not an original equipment manufacturer (OEM) part. It is engineered to meet or exceed OEM-level specifications using comparable materials. Our parts are manufactured in an ISO 9002 certified facility and are batch-inspected to ensure quality and consistency.
How fast is shipping and what does it cost?
We ship worldwide quickly, with typical transit times of 5–15 days for most regions. Standard shipping is free. If available for your location, expedited shipping options and their costs will be presented at checkout.
What is the warranty and return policy?
This part is covered by a 1-year warranty against manufacturing defects under normal marine use. If you encounter an issue, please contact our support team with your order details. Returns are accepted within our standard window for items that are unused and in their 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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