Marine V-Belt for MerCruiser 4.3L and 5.7L Engines – Replaces 57-816295Q and 57-816295T
Marine V-Belt for MerCruiser 4.3L and 5.7L Engines – Replaces 57-816295Q and 57-816295T is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
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Marine V-Belt for MerCruiser 4.3L and 5.7L Engines – Replaces 57-81...
Marine V-Belt for MerCruiser 4.3L and 5.7L Engines – Replaces 57-816295Q and 57-816295T is backordered and will ship as soon as it is back in stock.
Product Details
This marine replacement V-belt is designed for selected MerCruiser 4.3L and 5.7L stern-drive applications. It replaces the listed MerCruiser references 57-816295Q and 57-816295T and is intended for use in the engine belt-drive system. Confirm the engine application, belt routing, pulley arrangement, and original part number before ordering.
The belt is listed by Sierra as replacement number 18-15490 for the same MerCruiser reference numbers. The Mallory Marine reference 9-55007 is also supplied as a cross-reference from the product data.
- Replacement marine V-belt for MerCruiser stern-drive engines.
- Specified for MerCruiser 4.3L and 5.7L applications.
- Effective belt length: 52.5 inches.
- Top width: 29/64 inch.
- Single replacement belt; no pulley, tensioner, or installation hardware is included.
Part Number Matrix
Use the following manufacturer and aftermarket references to compare with the belt being replaced. Cross-reference numbers do not replace verification of the complete engine and pulley configuration.
| Brand or source | Part number | Reference type |
|---|---|---|
| MerCruiser | 57-816295Q | OEM reference |
| MerCruiser | 57-816295T | OEM reference |
| MerCruiser | 816295Q | Related reference format |
| MerCruiser | 816295T | Related reference format |
| Sierra | 18-15490 | Aftermarket cross-reference |
| Mallory Marine | 9-55007 | Aftermarket cross-reference |
Engine Compatibility
The company product data identifies this belt for MerCruiser 4.3L and 5.7L engines. The available records do not establish one universal year, horsepower, serial-number, or pulley configuration range for every engine carrying these displacements. Match the original belt and reference number, and verify the engine service information before installation.
| Brand | Engine displacement | Application | Reference numbers | Fitment note |
|---|---|---|---|---|
| MerCruiser | 4.3L | Stern-drive engine belt system | 57-816295Q, 57-816295T | Verify exact model, serial range, pulley arrangement, and belt routing. |
| MerCruiser | 5.7L | Stern-drive engine belt system | 57-816295Q, 57-816295T | Verify exact model, serial range, pulley arrangement, and belt routing. |
Technical Specifications
- Product type
- Marine V-belt
- Application
- MerCruiser stern-drive engine belt system
- Effective belt length
- 52.5 inches
- Effective belt length
- 1333.5 mm
- Top width
- 29/64 inch
- Top width
- Approximately 11.5 mm
- Construction
- V-belt construction with synthetic cord and rubber compression sections, based on the corresponding Sierra belt specification.
- Quantity
- 1 belt
What’s in the Box
- 1 x Marine V-belt
No pulley, tensioner, bracket, or additional installation hardware is included.
Installation Notes
- Disconnect the battery and allow the engine to cool before beginning work.
- Confirm that the replacement belt matches the removed belt in length, width, profile, and routing.
- Photograph or document the original belt routing before removal.
- Release the appropriate belt tension according to the engine service procedure.
- Remove the old belt without forcing it over the pulley edges.
- Route the replacement belt through the correct pulley grooves, ensuring that it is fully seated and not twisted.
- Set belt tension according to the engine manufacturer’s service instructions. Do not rely on a generic deflection measurement when a model-specific procedure is available.
- Rotate the pulleys by hand, where safe, to confirm correct tracking before starting the engine.
- Reconnect the battery, start the engine briefly, and inspect belt tracking and alignment. Stop immediately if the belt slips, walks, squeals excessively, or contacts an adjacent component.
Troubleshooting & FAQ
How do I confirm that this belt is correct for my engine?
First, match your original part number to 57-816295Q or 57-816295T and confirm that your engine is the listed MerCruiser 4.3L or 5.7L application. Then compare the belt dimensions—52.5-inch effective length and 29/64-inch top width—and verify the pulley arrangement and routing in the engine service information.
Is this belt for every MerCruiser 4.3L or 5.7L engine?
No single belt reference should be assumed to fit every model, year, serial range, or pulley configuration. The company data identifies the 4.3L and 5.7L engine families, but the exact installation must still be confirmed using the original belt, engine model information, and pulley arrangement.
What are the signs of a worn V-belt?
Common signs include cracking, fraying, glazing, missing material, abnormal squealing, belt dust, visible misalignment, or loss of accessory drive performance. Replace the belt if it shows damage or cannot maintain correct tension.
Can this belt be used for an alternator, water pump, or another accessory?
Use it only where the engine’s belt-routing diagram and original part reference specify this belt. Do not substitute it for another accessory belt solely because the belt appears similar; length, width, pulley location, and routing must all match.
Does this product include a pulley or belt tensioner?
No. This listing is for one replacement V-belt only. Pulley, tensioner, bracket, and other hardware are not included.
Is this an OEM belt?
This is an aftermarket replacement belt. The listed MerCruiser numbers are OEM reference numbers used to identify the intended replacement application; the belt itself is not represented as a genuine MerCruiser-branded part.
What should I do if the belt does not track correctly?
Stop the engine and check that the belt is seated in every pulley groove, the pulleys are aligned, the routing is correct, and the tension follows the engine manufacturer’s procedure. Do not continue operating the engine with a belt that slips, walks, or rubs.
Safety & Important Information
- Verify the original part number, belt dimensions, engine model, serial range, pulley arrangement, and routing before ordering.
- Disconnect the battery and keep hands, clothing, and tools away from rotating components.
- Do not operate the engine with a damaged, misaligned, or incorrectly tensioned belt.
- This is an aftermarket replacement component, not a genuine OEM-branded part.
- Professional installation is recommended when the engine service procedure or belt-drive layout is unfamiliar.
About Sea Sierra
- Marine Replacement Parts — We supply replacement components for common marine engine and stern-drive applications.
- Application-Focused Listings — Product references and fitment details are provided to help you compare the replacement with your original part.
- Support for Proper Matching — Always confirm the complete engine and component configuration before installation.
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