Water Pump V-Belt 104511-78780 for Yanmar 2GM 3GM 2YM 3YM 3HM YSM Marine Diesel
Water Pump V-Belt 104511-78780 for Yanmar 2GM 3GM 2YM 3YM 3HM YSM Marine Diesel
Product Overview
Sea water pump V-belt for Yanmar marine diesel engines, V-Belt M/19 section, replacing Yanmar 104511-78780 and 104511-78780E. It drives the raw water pump from the crankshaft pulley, so a worn belt shows up as a slipping squeal, a weak telltale at idle, or a belt that has stretched until the adjuster runs out of travel. Left alone, a failed belt stops the raw water pump and the engine overheats within minutes. Supplied as 1 x belt.
Specifications & Attributes
| Specification | Detail |
|---|---|
| Condition | New / New with tags |
| Type | Sea Water Pump Drive Belt |
| Belt Type | V-Belt M/19 |
| Engine Type | Yanmar marine diesel |
| Application | Seawater pump drive |
| Warranty | Standard |
OEM Cross Reference
| Brand | OEM Part Numbers |
|---|---|
| Yanmar | 104511-78780, 104511-78780E |
Compatible Engines
Fits the following Yanmar marine diesel engines:
| Series | Models |
|---|---|
| 2GM | 2GM, 2GM20 (20 HP), 2GM20-YEU, 2GM20F, 2GM20F-YEU, 2GMF |
| 3GM | 3GM, 3GM30 (30 HP), 3GM30-YEU, 3GM30F, 3GM30F-YEU, 3GMD, 3GMDF, 3GMF |
| 3HM | 3HM, 3HM35 (35 HP), 3HM35F, 3HMF |
| 2YM / 3YM | 2YM15 (15 HP), 3YM20 (20 HP), 3YM30 (30 HP) |
| YSM | YSM7 (7 HP) |
What's Included
| Component | Qty |
|---|---|
| Sea Water Pump V-Belt | 1 |
Condition & Warranty
| Item | Detail |
|---|---|
| Condition | New / New with tags |
| Warranty | Standard |
| Packaging | Sealed retail packaging |
Before You Buy
- Verify your engine model and serial number before ordering
- This is the M/19 section V-belt used on the sea water pump drive, not the alternator belt
- Check pulley alignment and bearing play in the raw water pump while the belt is off
- Re-tension after the first few hours of running
- 30-Day Easy Returns
- Free Worldwide Shipping
- OEM Quality Without the Markup
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Boat Owners' Review
Before You Buy
Frequently Asked Questions
What is your refund policy?
We offer a 14-day hassle-free return on all products. Items must be unused and in original packaging. Every XRmarine part is also covered by our 1-year warranty against manufacturing defects. If something is not right, email us at info@xrmarineparts.com — replacement or full refund, your choice.
See our full Refund Policy for complete details.
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See our full Shipping Policy.
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