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Alternator V-Belt – Fits Yanmar 4JH Series Marine Diesel Engines (Replaces 25132-004600)

Sale price $23.83 Regular price $38.00
Shipping calculated at checkout.

Alternator V-Belt – Fits Yanmar 4JH Series Marine Diesel Engines (Replaces 25132-004600) is backordered and will ship as soon as it is back in stock.


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 is a high-quality aftermarket Alternator V-Belt – Fits Yanmar 4JH Series Marine Diesel Engines (Replaces 25132-004600). It is designed for reliable power transmission from the crankshaft pulley to the alternator on 4-stroke marine diesel engines, including the 4JH2, 4JH3, 4JH-TE, and 4JH-HTE models. This belt is manufactured from durable rubber with a reinforced core to ensure longevity and consistent performance in fresh water cooled engine environments.

This part is a direct replacement for Yanmar 25132-004600 and 25132-004600E, and serves as an interchange for Gates Green Stripe A46 and REMF 6460.

  • Installation as an engine-driven belt.
  • Specifically designed for use on fresh water cooled engines.
  • Made from durable rubber with a reinforced internal core.

Part Number Matrix

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

Brand Part Number
Yanmar 25132-004600
Yanmar 25132-004600E
Gates Green Stripe A46
REMF 6460

Engine & Model Compatibility

Confirm your engine model/year in the table below.

This belt is confirmed to fit a wide range of Yanmar 4-stroke marine diesel engines. Please note the year limitation for the 4JH4-TE model.

Brand Model Stroke Years OEM Part No. Notes
Yanmar 4JH2-DTE 4-Stroke 25132-004600
Yanmar 4JH2-E 4-Stroke 25132-004600
Yanmar 4JH2-HTE 4-Stroke 25132-004600
Yanmar 4JH2-TE 4-Stroke 25132-004600
Yanmar 4JH2-UTE 4-Stroke 25132-004600
Yanmar 4JH3, 4JH3-TE 4-Stroke 25132-004600
Yanmar 4JH3-HTE, 4JH3-DTE 4-Stroke 25132-004600
Yanmar 4JHL, 4JHL-N, 4JHL-HTN 4-Stroke 25132-004600
Yanmar 4JH-DTE 4-Stroke 25132-004600
Yanmar 4JH-E 4-Stroke 25132-004600
Yanmar 4JH-HTE 4-Stroke 25132-004600
Yanmar 4JH-TE 4-Stroke 25132-004600
Yanmar 6PHM 4-Stroke 25132-004600
Yanmar 3JHLP 4-Stroke 25132-004600
Yanmar 4JH4-TE 4-Stroke Up to 07/2006 25132-004600 Not used on later 4JH4 models

Technical Specs

Product Type
Alternator V-Belt
Installation
Engine-driven belt
Connection
Looped belt
Housing Material
Rubber with reinforced core
Housing Color
Black
Dimensions
Approx. 48" (1220mm) outside length; A46 standard size
Fitting Type
V-belt
Other Technical Attributes
Used on fresh water cooled engines; Standard V-belt profile
Warranty
1 Year (varies by manufacturer)

What’s in the Box

  • 1 x V-Belt (25132-004600)

Installation Notes

  1. Ensure the engine is off and the battery is disconnected.
  2. Locate the alternator and identify the tensioning bolt and pivot bolt.
  3. Slightly loosen the pivot bolt and then loosen the tensioning bolt or adjuster to release tension on the old belt.
  4. Carefully slip the old belt off the alternator and crankshaft pulleys.
  5. Route the new belt around the pulleys, ensuring it is correctly seated in the V-grooves.
  6. Apply tension to the belt by tightening the tensioner. The correct tension typically allows for about 1/2 inch (13mm) of flex with firm thumb pressure.
  7. Once tension is set, securely tighten the alternator's tensioning and pivot bolts.
  8. Reconnect the battery, start the engine, and verify the belt is running smoothly without squealing.

Troubleshooting & FAQ

How do I know if this V-belt will fit my Yanmar engine?

This belt is designed for the Yanmar 4JH series and related models. The most reliable method is to check your engine's service manual or existing part for the number 25132-004600. You can also cross-reference your exact model and production year against our compatibility table.

The new belt seems extremely tight to install. Is this normal?

A snug fit is necessary for proper function, but it shouldn't require excessive force. Some users report a very tight fit, which can be due to minor variations in alternator positioning or aftermarket manufacturing tolerances. Ensure the alternator is fully loosened and pivoted to its closest position during installation. If it still won't fit, double-check your part number.

What are the signs of a worn alternator belt?

Common symptoms include a high-pitched squealing noise from the engine bay (especially on startup or under load), visible cracks, glazing, or fraying on the belt surface, and a flickering battery or charging system warning light on your dashboard, indicating the alternator isn't spinning consistently.

How often should this belt be replaced?

Preventative replacement intervals vary by engine use and conditions. A general guideline is to inspect the belt during every oil change and plan for replacement every 3-5 years or as recommended in your Yanmar service manual. Replace it immediately if you notice any signs of wear or damage.

Is this a genuine Yanmar OEM part?

This listing is for an aftermarket replacement, not an OEM component. It is built to meet or exceed OEM-level specifications using comparable materials. Our parts are manufactured in an ISO 9002 certified facility and are batch-inspected for quality and consistency.

What are the shipping speed and cost?

We ship worldwide quickly, with typical transit times of 5–15 days. Standard shipping is free to most locations. Expedited shipping options, where available, 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 operating 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 full policy page or reach out for instructions.

Safety & Important Info

  • Verify images and specifications against 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, typically arriving in 5–15 days.
  • Manufacturer-Direct Value — Fair pricing on high-quality components without compromising on materials or quality control.

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