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Yanmar Marine Parts
THERMOSTAT O
Availability: 2-7 days
Shipping: Worldwide
Price
On Request
Quote reference: Part No. YM-129150-49811
Need help identifying this part?THERMOSTAT O-RING - 4TNV88-BDHQ / 4TNV88-BDHQ(T) / 4TNV88-BDSA
Product Details
Part Number
YM-129150-49811
Description
THERMOSTAT O-RING - 4TNV88-BDHQ / 4TNV88-BDHQ(T) / 4TNV88-BDSA
Brand
Yanmar
Category
Others
Availability
2-7 days
Shipping
Worldwide
Price
On Request
Product Description
Yanmar Engine thermostat YM-129150-49811
1. Product Overview
Yanmar Engine thermostat YM-129150-49811 is listed under source title “THERMOSTAT O”. It is classified for Batch 4 as engine thermostat within the engine cooling control system. The source record does not establish an exact engine model. Confirm the complete engine model, serial number, arrangement, and installed reference before ordering.
2. Function and Operating Principle
A thermostat regulates coolant flow according to temperature so the engine can warm up and remain within its intended operating range. Opening temperature, lift, bypass arrangement, housing, and sealing must match the cooling system.
A temperature-sensitive element moves the valve as coolant temperature changes. This redirects or increases flow through the radiator or heat exchanger while coordinating with the bypass circuit.
3. Application Status
| Manufacturer / brand | Yanmar |
|---|---|
| Part number | YM-129150-49811 |
| Component category | Engine thermostat |
| System | Engine cooling control |
| Evidence level | C — Component identity only |
| Engine application | Not established by the supplied record |
4. Typical Signs That Inspection May Be Required
| Observation | Possible significance |
|---|---|
| Slow warm-up or low operating temperature | May be associated with a thermostat stuck open or other cooling-system conditions. |
| High or fluctuating temperature | Can involve thermostat operation, coolant level, flow, pumps, restriction, or loading. |
| Coolant leakage at the housing | May involve seals, surfaces, fasteners, or housing damage. |
| Uneven hose or housing temperature | Requires controlled diagnosis of coolant circulation. |
These observations are inspection triggers rather than a confirmed diagnosis. Evaluate the complete engine system and follow the applicable manufacturer service information.
5. Inspection and Replacement Guidance
- Allow the cooling system to depressurize and cool safely.
- Inspect coolant condition, housing, seals, bypass, pump, and flow restrictions.
- Test only by the approved temperature and lift procedure.
- Confirm opening specification and engine arrangement.
6. Information Required Before Ordering
- Complete engine or equipment model.
- Engine serial number and arrangement or configuration number.
- Installed part reference and clear photographs of the identification label.
- Installation position and related assembly information.
Compatibility notice: Verify YM-129150-49811 against serial-number-specific parts documentation before purchase or installation. Do not select the component by appearance or part-number similarity alone.