Marine Belt for Volvo Penta D4-260, D6-350 and D6-370 (21407026, 3583963)
Marine Belt for Volvo Penta D4-260, D6-350 and D6-370 (21407026, 3583963) 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.
International delivery times may vary due to customs processing.
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Marine Belt for Volvo Penta D4-260, D6-350 and D6-370 (21407026, 35...
Marine Belt for Volvo Penta D4-260, D6-350 and D6-370 (21407026, 3583963) is backordered and will ship as soon as it is back in stock.
Product Details
This replacement marine belt is designed for selected Volvo Penta stern-drive and out-drive applications, including the D4-260, D6-350, and D6-370 engine models. It is supplied as one belt for the engine belt-drive system.
Use the OEM reference numbers and exact engine model to confirm compatibility before ordering. The company catalog identifies this belt with Volvo Penta reference numbers 21407026 and 3583963.
- Replacement marine belt for selected Volvo Penta applications.
- Single-belt product, not a kit.
- Fitment is limited to the engine models listed below.
Part Number Matrix
These are the Volvo Penta reference numbers identified for this belt. Confirm the number on your original belt or engine parts documentation before purchase.
| Brand | OEM Reference Number |
|---|---|
| Volvo Penta | 21407026 |
| Volvo Penta | 3583963 |
Engine & Model Compatibility
The company fitment record lists the following Volvo Penta engine models. No general year range or serial-number range is specified, so verify the exact model and reference number for your engine.
| Brand | Engine Model | OEM Reference Numbers |
|---|---|---|
| Volvo Penta | D4-260 | 21407026, 3583963 |
| Volvo Penta | D6-350 | 21407026, 3583963 |
| Volvo Penta | D6-370 | 21407026, 3583963 |
Technical Specs
- Product Type
- Marine belt
- Application
- Selected Volvo Penta stern-drive and out-drive engine applications
- Listed Engine Models
- D4-260, D6-350, and D6-370
- OEM Reference Numbers
- 21407026 and 3583963
- Product Quantity
- One belt
What’s in the Box
- 1 × Marine replacement belt
Installation Notes
- Confirm that your engine model and original belt reference number match the application information above.
- Turn off the engine, allow it to cool completely, and disconnect the battery before beginning work.
- Record the existing belt routing before removal.
- Release the belt tension according to the engine manufacturer's service procedure and remove the old belt.
- Inspect the pulleys and tensioning components for wear, corrosion, contamination, or damage before installation.
- Install the replacement belt along the original routing and make sure it is fully seated in every pulley groove.
- Adjust belt tension according to the engine manufacturer's specifications. Do not rely on a generic deflection measurement when a model-specific procedure is available.
- Reconnect the battery, run the engine briefly, and check that the belt tracks correctly without slipping, fraying, or abnormal noise.
- Stop the engine and recheck the installation after the initial run.
Troubleshooting & FAQ
Which engines are listed for this belt?
The company fitment record lists Volvo Penta D4-260, D6-350, and D6-370 engines. Confirm the exact model and OEM reference number before ordering.
Which OEM reference numbers are associated with this belt?
The listed Volvo Penta reference numbers are 21407026 and 3583963.
Does this listing include a belt kit or multiple components?
No. This is a single replacement belt. Additional pulleys, tensioners, fasteners, or other components are not included.
How can I tell whether my belt needs replacement?
Inspect the belt for cracking, fraying, glazing, missing ribs, contamination, or other visible damage. Squealing, chirping, slipping, or abnormal belt tracking can also indicate a problem. Diagnose the complete belt-drive system before replacing the belt.
Are year and serial-number ranges provided?
No specific year or serial-number range is provided in the company fitment record. Match your exact engine model and reference number rather than relying on a general year range.
What should I do if my engine is not listed?
Do not assume compatibility based only on horsepower or a similar-looking belt. Check your engine documentation or the number printed on the original belt and compare it with 21407026 or 3583963 before ordering.
Shipping speed and cost?
Shipping options, delivery estimates, and applicable costs are shown at checkout based on the destination and service selected.
Safety & Important Info
- Verify the exact engine model and OEM reference number before purchase.
- Do not install the belt on an unlisted engine solely because the belt appears similar.
- Always follow the engine manufacturer's service procedure for belt routing and tension.
- Disconnect the battery and keep hands, clothing, and tools away from moving components during testing.
- Professional installation is recommended when the correct routing or tension procedure is uncertain.
About Sea Sierra
- Marine Parts Support — We provide replacement components for marine engine and stern-drive applications.
- Application-Focused Listings — Product information is organized around listed engine models and reference numbers.
- Global Fulfillment — Available shipping options and delivery estimates are presented at checkout.
Payment & Security
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