Replacement Alternator Belt for Yanmar 2GM20, 2GM20-YEU & 2GMLP – Reference 25132-003100
Replacement Alternator Belt for Yanmar 2GM20, 2GM20-YEU & 2GMLP – Reference 25132-003100 is backordered and will ship as soon as it is back in stock.
Worry-free returns
Worry-free returns
Shop with confidence. If you’re not completely satisfied, eligible items may be returned within the return window, provided they are unused and in original packaging.
If the return is due to our error or a defective item, we’ll make it right.
Please contact us before returning any item.
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.
Tracking information will be provided once your order ships.
Replacement Alternator Belt for Yanmar 2GM20, 2GM20-YEU & 2GMLP...
Replacement Alternator Belt for Yanmar 2GM20, 2GM20-YEU & 2GMLP – Reference 25132-003100 is backordered and will ship as soon as it is back in stock.
Product Details
This replacement alternator belt is listed for Yanmar Marine inboard engines including the 2GM20, 2GM20-YEU, and 2GMLP. The belt is designed for the engine charging system and runs between the engine pulleys to drive the alternator.
The company catalog identifies this product as a single marine belt and lists Yanmar reference number 25132-003100. Confirm the model designation and the number on your existing belt before ordering.
- Replacement belt for the alternator drive system.
- Listed for selected Yanmar 2GM-series marine inboard engines.
- Supplied as one individual belt.
Part Number Reference
Use the following reference to compare the belt with your existing part and engine documentation.
| Brand | Reference Number | Application |
|---|---|---|
| Yanmar | 25132-003100 | Alternator belt reference listed for this product. |
Engine Compatibility
The company fitment record lists the following Yanmar Marine inboard engine models. Keep the complete model designation together when checking compatibility.
| Brand | Engine Model | Stroke | Reference Number | Notes |
|---|---|---|---|---|
| Yanmar Marine Inboard | 2GM20 | Not specified | 25132-003100 | Confirm the exact model designation before ordering. |
| Yanmar Marine Inboard | 2GM20-YEU | Not specified | 25132-003100 | Confirm the exact model designation before ordering. |
| Yanmar Marine Inboard | 2GMLP | Not specified | 25132-003100 | Confirm the exact model designation before ordering. |
Technical Information
- Product Type
- Marine alternator belt
- Product Configuration
- Single belt
- Listed Engine Brand
- Yanmar Marine Inboard
- Listed Engine Models
- 2GM20, 2GM20-YEU, and 2GMLP
- Reference Number
- 25132-003100
- Dimensions
- Not specified in the company product record. Compare the replacement belt with the original before installation.
- Material
- Not specified in the company product record.
What’s in the Box
- 1 x Replacement alternator belt
Installation Notes
- Turn off the engine, allow it to cool, and prevent accidental starting before beginning work.
- Disconnect the battery if required by the engine manufacturer’s service procedure.
- Inspect the original belt routing and identify the pulleys driven by the belt.
- Loosen the alternator adjustment hardware enough to release belt tension.
- Remove the old belt and inspect the pulley grooves for wear, corrosion, contamination, or damage.
- Install the replacement belt along the original routing, making sure it is seated correctly in every pulley groove.
- Adjust the belt tension according to the Yanmar engine service manual. Do not overtighten the belt.
- Tighten the adjustment and mounting hardware to the manufacturer’s specified torque.
- Reconnect the battery if it was disconnected, then run the engine briefly and check belt tracking and operation.
- Stop the engine and recheck the belt after operation. Adjust only according to the engine manufacturer’s instructions.
Troubleshooting & FAQ
How do I know if this belt fits my engine?
Check that your engine is a Yanmar 2GM20, 2GM20-YEU, or 2GMLP and compare the existing belt with reference number 25132-003100. Model, designation, pulley arrangement, and belt dimensions should all be checked before ordering.
Is this belt for the alternator?
Yes. The company product record identifies it as an alternator belt for the listed Yanmar Marine inboard applications.
How many belts are included?
This is a single-belt product. The package contains one replacement alternator belt.
What should I check before installation?
Check the belt routing, pulley grooves, belt condition, and the exact engine model. Replace or repair worn pulleys and follow the Yanmar service manual for tension and torque specifications.
What are signs that the belt may need attention?
Inspect for cracking, fraying, glazing, contamination, abnormal noise, slipping, or visible damage. Charging-system problems may have several causes, so inspect the belt and the complete charging system before replacing parts.
Is this an OEM Yanmar belt?
The product is listed as a replacement belt with Yanmar reference number 25132-003100. The available product record does not explicitly identify it as genuine Yanmar original equipment.
Safety & Important Information
- Verify the exact engine model and the original belt reference before purchase.
- Do not install a belt that differs in profile, length, or fit from the original application.
- Keep hands, clothing, and tools clear of rotating components while the engine is running.
- Follow the applicable Yanmar service manual for belt tension, fastener torque, and maintenance intervals.
- Professional installation is recommended if the belt routing or adjustment procedure is uncertain.
About Sea Sierra
- Marine replacement parts selected for practical service and maintenance applications.
- Clear product references and application information to help support accurate part selection.
- Global fulfillment options are available where offered at checkout.
Payment & Security
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
