25112-003601 V Belt for Yanmar 2GM 3GM | JLM Marine

Vendor: JLM Marine
Availability: In Stock
Product Type: Belt
$25.99
$25.99
Subtotal: $25.99

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Alternator V - Belt – Fits Yanmar 2GM, 3GM Series Diesel Engines (Replaces 25112 - 003601) - JLM Marine Boat Parts Limited

25112-003601 V Belt for Yanmar 2GM 3GM | JLM Marine

$25.99

25112-003601 V Belt for Yanmar 2GM 3GM | JLM Marine

$25.99

V Belt for Yanmar 2GM 3GM Marine Engines – OEM 25112-003601

This high-quality V belt is engineered to fit Yanmar 2GM and 3GM series marine inboard engines, including models such as 2GM20, 3GM30, and their variants. Designed as a direct replacement for OEM part number 25112-003601, this belt ensures reliable power transmission and smooth engine operation in marine environments.

Built to OEM specifications, this aftermarket V belt provides dependable performance for a wide range of Yanmar marine engine models, including 2GM20F-YEU, 2GM20FC-YEU, 2GMFL, 2GMFY(E)-E, 3GM30F-YEU, 3GM30FC-YEU, 3GMFLE, 3GMFY-E, and 3GMFYE-E(HE).

  • Direct replacement for Yanmar OEM part number 25112-003601
  • Engineered for marine-grade durability and heat resistance
  • Simple installation with no modifications required

Part Number Cross-Reference

Use this table to confirm the OEM part number for your Yanmar engine:

Brand Part Number
Yanmar 25112-003601

Compatible Engine Models

Confirm your engine model/year in the table below.

Brand Model
Yanmar 2GM20F-YEU
Yanmar 2GM20FC-YEU
Yanmar 2GMFL
Yanmar 2GMFY(E)-E
Yanmar 3GM30F-YEU
Yanmar 3GM30FC-YEU
Yanmar 3GMFLE
Yanmar 3GMFY-E
Yanmar 3GMFYE-E(HE)

Technical Specifications

Specification Value
OEM Part Number 25112-003601
Application Marine Inboard Engine
Compatible Engine Series Yanmar 2GM, 3GM

Package Contents

This package includes:

  • 1 × V Belt

Installation Guide

  1. Safety First: Disconnect the battery and ensure the engine is completely cool before beginning work.
  2. Access the Belt: Remove any engine covers or guards that obstruct access to the V belt and pulleys.
  3. Release Tension: Loosen the alternator or accessory mounting bolts to reduce tension on the old belt. Slide the component toward the engine block to create slack.
  4. Remove Old Belt: Carefully slide the worn belt off the pulleys and inspect the pulleys for wear, cracks, or debris.
  5. Clean Pulleys: Wipe down all pulley surfaces with a clean cloth to remove any oil, dirt, or residue that could cause slipping.
  6. Position New Belt: Route the new V belt around the crankshaft pulley first, then loop it over the alternator or accessory pulley following the original path.
  7. Apply Tension: Slide the alternator or accessory component away from the engine to apply proper tension. The belt should deflect approximately ½ inch when pressed midway between pulleys.
  8. Tighten Mounting Bolts: Secure the alternator or accessory mounting bolts firmly, ensuring the component does not shift.
  9. Check Alignment: Verify that the belt sits squarely in all pulley grooves without twisting or misalignment.
  10. Reinstall Covers: Replace any engine guards or covers that were removed during installation.
  11. Reconnect Battery: Restore battery connection and start the engine to confirm smooth operation without squealing or slipping.
  12. Final Inspection: After running the engine for a few minutes, recheck belt tension and adjust if necessary.

Troubleshooting & FAQ

Q: How do I confirm this V belt fits my Yanmar engine?
A: Cross-reference your engine model number with the compatibility table above. If your engine uses OEM part number 25112-003601, this belt is the correct replacement. Always verify against your original part before ordering.

Q: What are the signs that my V belt needs replacement?
A: Common symptoms include squealing noises during engine operation, visible cracking or fraying on the belt surface, glazing or shiny appearance, alternator undercharging, or belt slipping off pulleys. Replace the belt immediately if any of these signs appear.

Q: How often should I replace the V belt on my Yanmar marine engine?
A: Inspect the V belt every 100 operating hours or annually, whichever comes first. Replace it every 2–3 years or sooner if you notice wear, cracking, or performance issues. Marine environments accelerate wear due to heat, salt, and vibration.

Q: Can I install this belt myself, or do I need a professional?
A: If you have basic mechanical skills and tools, installation is straightforward following the guide above. However, proper tension adjustment is critical—professional installation is recommended if you're unsure to avoid slipping or premature wear.

Q: What's the difference between this aftermarket belt and the OEM Yanmar belt?
A: This is an aftermarket replacement part built to OEM specifications using comparable-grade materials. We manufacture in an ISO9002-certified facility with rigorous quality control. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.

Q: OEM vs. Aftermarket?
A: This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.

Q: How fast do you ship and how much does it cost?
A: We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.

Q: What is your warranty and return policy?
A: This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.

Important Notes

  • Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
  • This product is an aftermarket replacement part and is not an OEM component.
  • Professional installation is recommended to ensure safety and optimal performance.

Why Choose JLM MARINE?

  • Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
  • Fast Global Shipping: Free delivery worldwide in 5–15 days.
  • Direct from Manufacturer: Competitive pricing without compromising quality.

We can ship to virtually any address in the world with free shipping available for most regions.

For our typical US and Canadian customers , our shipping timeframes are as follows:

  • Amazon FBA: orders will be delivered within 1-5 business days after placing the order (during certain special periods such as major promotions, Christmas, etc., the delivery time of Amazon FBA may be affected).
  • US warehouse shipment: orders will be delivered within 5 days after placing the order.
  • China warehouse shipment: orders will be delivered about 12 days after placing the order.

When you place an order, we will estimate shipping and delivery dates for you based on the availability of your items and the shipping options you choose. Depending on the shipping provider you choose, shipping date estimates may appear on the shipping quotes page.

Please also note that the shipping rates for many items we sell are weight-based. The weight of any such item can be found on its detail page. To reflect the policies of the shipping companies we use, all weights will be rounded up to the next full pound.

Founded in 2002, JLM Marine has established itself as a dedicated manufacturer of high-quality marine parts, based in China. Our commitment to excellence in manufacturing has earned us the trust of top marine brands globally.

As a direct supplier, we bypass intermediaries, which allows us to offer competitive prices without compromising on quality. This approach not only supports cost-efficiency but also ensures that our customers receive the best value directly from the source.

We are excited to expand our reach through retail channels, bringing our expertise and commitment to quality directly to boat owners and enthusiasts worldwide.

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