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SKU:
NLT2T03467
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Thermostat 600-421-6120 / 600-421-6110 for Komatsu 4D95 / 6D95 Engines
$35.49
In Stock
$35.49
Sale price
$35.49
Regular price
This engine thermostat cross-references Komatsu 600-421-6120 / 600-421-6110 for compatible 4D95 and 6D95-series applications.
Estimated delivery between
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Compatible Models
We do our best to list all compatible models. Although this may be the part you need, your exact model may not appear below.
Compatible equipment / model
| Brand / Family | Compatible Applications |
|---|---|
| Komatsu engines | 4D95L / 6D95-series configurations using the listed thermostat |
| Komatsu equipment examples | PC60/PC70, PC200-5, PC220-5 and related 95-series applications; verify engine and thermostat number |
Product Overview
The thermostat regulates coolant flow so the engine warms normally and stays within its intended operating range under load. A thermostat stuck closed can contribute to rapid overheating; one stuck open can cause slow warm-up and low operating temperature.
Komatsu 95-series machines use different thermostat housings and engine variants across generations.
Key Features & Performance
- Regulates engine temperature: Controls coolant flow between the engine and radiator as operating temperature changes.
- Addresses overcooling or overheating: A stuck-open thermostat can cause slow warm-up, while a stuck-closed unit can cause rapid overheating.
- Specification-sensitive: Part number, engine code and opening temperature should match the machine service data.
- Product-specific note: Komatsu 95-series machines use different thermostat housings and engine variants across generations.
Technical Specifications
- Component: Engine coolant thermostat
- Service-manual reference: 95-series cooling-system documentation lists 82°C cracking temperature for certain 6D95/4D95 configurations
Replaces / Reference Part Numbers
600-421-6120, 600-421-6110
Common Replacement Reasons
- Engine runs too cool because the thermostat is stuck open
- Rapid overheating caused by a thermostat that will not open
- Cooling-system service where the thermostat fails temperature testing
Frequently Asked Questions
How do I confirm this is the correct part?
Confirm the original thermostat number, engine code and opening-temperature specification in the machine service data.
Is this an OEM part?
Unless the listing is explicitly identified as genuine/OEM in the product data, treat it as a replacement component. Use the verified reference numbers, equipment application and physical configuration above to match your original part.
What should I check before installation?
The thermostat part number and engine code should be checked rather than assuming every PC200/PC300 uses the same unit.
Fitment note: Equipment manufacturers may use different components within the same model family based on engine, serial number or production date. Confirm the original part number and machine/engine details before ordering.