Forklift Thermostat

Forklift Thermostat: 76°C & 82°C Engine Coolant Control Valves for Diesel Forklifts

The thermostat is a $10 wax-pellet valve that controls whether coolant circulates through the radiator or recirculates inside the engine block. When the engine is cold, the thermostat stays closed, forcing coolant to bypass the radiator so the engine reaches operating temperature faster. At the rated opening temperature (76°C or 82°C), the wax pellet expands, opening the valve and allowing hot coolant to flow through the radiator for cooling. A thermostat stuck closed causes the engine to overheat within minutes — the most common thermostat failure mode. A thermostat stuck open prevents the engine from reaching operating temperature, causing incomplete combustion, increased fuel consumption, and carbon buildup.

Kingstream supplies replacement thermostats for Daewoo, Foton, HELI, Toyota, Komatsu, and CAT diesel engines. Every thermostat is tested for opening temperature accuracy and full-open stroke distance before shipment.

76°C vs 82°C Thermostats:

The opening temperature is stamped on the thermostat body. Using the wrong temperature rating affects engine performance: a 76°C thermostat opens earlier, keeping the engine cooler — preferred for hot climates and continuous heavy-load operation. An 82°C thermostat keeps the engine hotter for better combustion efficiency and reduced emissions — standard for temperate climates and normal-duty operation. Always replace with the same temperature rating as the original, unless operating conditions have changed significantly.

When to Replace Your Thermostat:

• Engine overheats despite full coolant, functioning radiator, and working water pump → Thermostat stuck closed. Confirm by feeling the upper radiator hose — if it stays cold while the engine overheats, the thermostat isn’t opening
• Engine takes excessively long to reach operating temperature, heater blows cold → Thermostat stuck open. Coolant is constantly circulating through the radiator, preventing warmup
• Temperature gauge fluctuates erratically — hot then cold then hot again → Thermostat is sticking intermittently. Replace before it sticks closed permanently
• Coolant leaking from the thermostat housing → Housing gasket has failed. Replace the thermostat and gasket together
• Any cooling system overhaul (water pump, radiator replacement) → Preventive replacement. The thermostat is inexpensive and accessible during these repairs

OEM Cross-Reference / Available Models:

Need a specific thermostat by engine model? Send us your engine model and temperature rating →

Compatible Forklift Brands:
Daewoo DE12, Foton Aumark, HELI, Toyota, Komatsu, CAT diesel.

Browse our complete forklift engine cooling system catalog.