Engine Thermostat

Key Functions:

• Cold Start: Blocks coolant circulation for faster warm-up

• Temperature Regulation: Modulates flow to maintain 90-110°C operating range

• Overheat Protection: Full-open position during cooling system overload

Technical Features:

• Wax Pellet: Expands precisely ~0.1mm/°C

• Jiggle Valve: Allows air bleeding during refills

• Bypass Channel: Maintains minimal circulation when closed

Failure Modes:

• Stuck open: Extended warm-up, poor heater performance

• Stuck closed: Rapid overheating risk

• Weak spring: Erratic temperature control

Modern developments include:

• Electronically-controlled smart thermostats

• Integrated temperature sensors

• Fail-safe designs for hybrid vehicles

This simple but critical component improves fuel efficiency by 3-5% while protecting engine components from thermal stress.

Specification Of Thermostat

OEM NO	Cars	Universal original number	Picture	(D1*d2*A)			Temperature
069121113	VW AUDI			66.7	35	24	87
075121113D,96101599 ,133818,96080220,93501145，93501386,96159513,1612191,6182480,133814,133764,133768,133820,133825,7700665226,7700 697157,133764	VW, CITROEN, PEUGEOT, RENAULT			66.7	29	24	87
025121113E, 025121113F，025121113D	VW,AUDI			66.7	29	24.5	87
1102000915 OO22031675 OO22034575,0032037475,0032037975,	BENZ			66.7	43	25.5	79
1710953 11531713040	B.M.W			66.6	35	25	80
7511083 11531712043 11537511083，1733803，1743542，11531733803，11531743528，11531743542，1743542	LAND ROVER B.M.W			66.6	35	26	88
6012000115，6022000115， 0032039875，6062000475，6062030175	BENZ			66.6	43	26	80
	AD5缸			66.7	35	24.5	87
078121113J,077121113,078121113C,078121113F,078121113J,077121113,078121113,078121113 C,078121113 F	VW AUDI			66.7	35	24.5	87