V-Belt for Yanmar 2GM20, 3GM30 & 3HM – OEM 128670-77350
V-Belt for Yanmar 2GM20, 3GM30 & 3HM – OEM 128670-77350 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.
V-Belt for Yanmar 2GM20, 3GM30 & 3HM – OEM 128670-77350
V-Belt for Yanmar 2GM20, 3GM30 & 3HM – OEM 128670-77350 is backordered and will ship as soon as it is back in stock.
Product Details
This replacement V-belt is intended for Yanmar Marine Inboard 2GM20, 3GM30, and 3HM engines. It is used in the engine belt-drive system, including the alternator drive application shown in the supporting belt catalog reference.
The belt corresponds to Yanmar OEM part number 128670-77350. Confirm the model designation and the part number from your engine documentation or the belt being replaced before ordering.
- Replacement belt for specified Yanmar marine inboard engines.
- Single belt supplied; this is not a repair kit.
- Suitable for service replacement when the existing belt matches the specified OEM reference.
- Install and tension according to the engine manufacturer’s service instructions.
Part Number Reference
| Brand | Part Number |
|---|---|
| Yanmar | 128670-77350 |
Engine Compatibility
This belt is listed for the following Yanmar Marine Inboard engine models. Model, year, serial number, and engine configuration can affect fitment, so verify the complete engine identification before installation.
| Brand | Engine Model | Stroke | OEM Part Number | Application |
|---|---|---|---|---|
| Yanmar | 2GM20 | Not specified | 128670-77350 | Marine inboard engine belt drive |
| Yanmar | 3GM30 | Not specified | 128670-77350 | Marine inboard engine belt drive |
| Yanmar | 3HM | Not specified | 128670-77350 | Marine inboard engine belt drive |
Technical Specifications
- Product Type
- Marine engine V-belt
- Brand Application
- Yanmar Marine Inboard
- OEM Reference
- 128670-77350
- Compatible Models
- 2GM20, 3GM30, and 3HM
- Installation
- Replacement belt for the existing belt-drive system
- Quantity
- 1 belt
- Drive Application
- Engine belt drive, including the alternator drive application where specified by the engine configuration
What’s in the Box
- 1 x replacement V-belt
Installation Notes
- Turn the engine off, allow it to cool, and disconnect the battery before beginning work.
- Identify the existing belt and note its routing around each pulley.
- Release the belt tension using the adjustment method specified for your engine.
- Remove the old belt and inspect the pulleys for contamination, damage, or abnormal wear.
- Compare the replacement belt with the removed belt and confirm the OEM reference and profile are correct.
- Route the new belt over the pulleys without forcing or twisting it.
- Adjust the belt tension according to the Yanmar service manual for your exact engine configuration.
- Tighten all adjustment and mounting hardware, then rotate the engine by hand if appropriate to check belt tracking.
- Reconnect the battery, start the engine, and inspect the belt for correct tracking and unusual noise.
Troubleshooting & FAQ
How do I confirm that this belt fits my engine?
Check that your engine is a Yanmar Marine Inboard 2GM20, 3GM30, or 3HM and that the existing belt or service documentation identifies OEM part number 128670-77350. If the model, serial number, or belt reference differs, consult the engine service documentation before ordering.
What are common signs of a worn engine belt?
Common warning signs include squealing during startup or acceleration, visible cracking, fraying, glazing, abnormal looseness, and inconsistent operation of belt-driven accessories. Inspect the belt and pulleys together because pulley wear or misalignment can cause premature belt failure.
How often should I inspect or replace the belt?
Inspect the belt during routine engine maintenance and before extended operation. Replace it when it shows cracking, fraying, glazing, damage, excessive stretch, or incorrect tension, or follow the maintenance interval specified in the service manual for your exact engine.
Is this a complete belt kit?
No. This listing is for one replacement V-belt only. It does not include pulleys, tensioners, fasteners, or other engine components.
Can I install this belt myself?
Belt replacement may be suitable for an experienced boat owner, but correct routing and tension are essential. Use the procedure and tension specification in the service manual for your engine. If you are unsure how to release or adjust the belt, have the work performed by a qualified marine technician.
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.
