What Causes a Thermostat to Leak?
2 Answers
The reasons for a thermostat leaking are as follows: 1. Coolant Leakage: The installation position of the thermostat is precisely at the connection point of the two circulation systems' pipelines. The presence of an interface in the water channel at this location poses a risk. Although the thermostat is equipped with sealing components, coolant leakage can still occur. 2. Engine Overheating: When the thermostat is stuck in the position that closes the large circulation loop, even if the coolant temperature can soften the paraffin, the large circulation loop still cannot be opened. In this situation, the coolant itself cannot dissipate heat, quickly leading to engine overheating.
I've driven quite a few cars and encountered this issue several times. The most common cause of thermostat leakage is the aging and deformation of the sealing ring. The high temperature and pressure in the coolant can corrode this component over time, causing the rubber to become brittle and crack, leading to leaks. Alternatively, the thermostat body itself might have cracks, possibly due to over-tightening during assembly or damage from impact. If you notice the coolant level dropping rapidly or green/pink stains on the ground, there's a high chance it's leaking here. You should get it fixed immediately; otherwise, engine overheating could cause a blown gasket, with repair costs running into thousands. During routine checks, pop the hood to inspect for leaks and regularly replace the entire coolant system to prevent corrosion. Don't wait until the temperature gauge spikes red while driving to panic—safety first.
