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Serpentine Drive Belt – Fits Volvo Penta D4 & D6 (Replaces 21405493, 23324914, 3817787)

Regular price $49.39

Worry-free returns

You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).

You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).

If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.

Delivery and Shipping

Free standard shipping on all orders under 1 KG

If you have any questions, feel free to email us at info@sierramarines.com, and we’ll get back to you within 20–36 hours.

Product Details

This high-performance Serpentine Drive Belt is engineered for a precise fit on Volvo Penta D4 and D6 series diesel marine engines. It is a vital component for powering engine accessories, including the water pump and alternator, ensuring reliable operation out on the water.

This belt is a direct replacement for Volvo Penta part numbers 21405493, 23324914, and 3817787.

  • Powers essential engine accessories for full functionality.
  • Designed for external engine installation.
  • Constructed from durable rubber with polyester reinforcement.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Brand Part Number Superseded By Notes
Volvo Penta 23324914 Current OEM part number.
Volvo Penta 21405493 23324914
Volvo Penta 3817787 23324914

Engine & Model Compatibility

Confirm your engine model in the table below. This belt fits all horsepower variants of the listed Volvo Penta D4 and D6 engines.

Brand Model Rated HP Stroke OEM Part No.
Volvo Penta D4-180 180 4-Stroke 21405493, 23324914, 3817787
Volvo Penta D4-210 210 4-Stroke 21405493, 23324914, 3817787
Volvo Penta D4-225 225 4-Stroke 21405493, 23324914, 3817787
Volvo Penta D4-260 260 4-Stroke 21405493, 23324914, 3817787
Volvo Penta D4-300 300 4-Stroke 21405493, 23324914, 3817787
Volvo Penta D6-280 280 4-Stroke 21405493, 23324914, 3817787
Volvo Penta D6-300 300 4-Stroke 21405493, 23324914, 3817787
Volvo Penta D6-310 310 4-Stroke 21405493, 23324914, 3817787
Volvo Penta D6-330 330 4-Stroke 21405493, 23324914, 3817787
Volvo Penta D6-350 350 4-Stroke 21405493, 23324914, 3817787
Volvo Penta D6-370 370 4-Stroke 21405493, 23324914, 3817787
Volvo Penta D6-400 400 4-Stroke 21405493, 23324914, 3817787
Volvo Penta D6-435 435 4-Stroke 21405493, 23324914, 3817787

Technical Specs

Product Type
Serpentine Drive Belt
Installation
Engine External
Fuel Type
Diesel
Material
Rubber with Polyester Reinforcement
Function
Powers engine accessories including water pump, alternator, and other components
Warranty
1 year against manufacturing defects

What’s in the Box

  • 1 x Serpentine Drive Belt (Replaces 21405493, 23324914, 3817787)

Installation Notes

  1. Safety First: Disconnect the battery and ensure the engine is cool before starting.
  2. Locate the Belt: Identify the existing serpentine belt routing and the automatic tensioner pulley. Taking a photo can be helpful for reference.
  3. Release Tension: Use an appropriate wrench or breaker bar to rotate the tensioner, releasing pressure on the belt.
  4. Remove Old Belt: Carefully slide the old belt off the pulleys.
  5. Route New Belt: Following your photo or the engine diagram, route the new belt over all pulleys, leaving the tensioner pulley for last.
  6. Apply Tension: Rotate the tensioner again and slip the new belt onto the final pulley. Slowly release the tensioner to apply tension.
  7. Final Check: Double-check that the belt is correctly seated in all pulley grooves. Reconnect the battery and start the engine to verify smooth operation.

Troubleshooting & FAQ

How do I know if this belt fits my specific D4 or D6 engine variant (e.g., D4-225A-F)?

This belt is designed for all horsepower versions of the base D4 and D6 engines and serves as a direct cross-reference for the OEM part numbers listed. However, we always recommend verifying the required part number for your specific engine model and serial number using your service manual before purchase.

What are common signs my serpentine belt is failing?

Look for visible cracks, fraying, glazing, or missing ribs on the belt. Audible signs include squealing or chirping sounds from the engine bay, which may worsen on startup or under load. Failure can also lead to alternator charging issues or engine overheating.

What is the recommended replacement interval?

Replacement intervals depend on usage and operating conditions. As a general guideline, you should inspect the belt during your annual service and plan to replace it every 3-5 years, or as specified by your Volvo Penta engine's maintenance schedule.

Can I install this serpentine belt myself?

For individuals with good mechanical experience and the correct tools (e.g., a tensioner wrench/bar), this is a manageable task. However, because proper belt tension and alignment are critical for engine health, professional installation is recommended for safety and performance.

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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