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Frequently asked questions about cars and motorcycles

Coolant Doesn’t Seem to Decrease: Here are the Reasons Why It Might

Model: (Various brands) Various
Part: Radiator

If you often find yourself topping up the radiator fluid, you may have one of two issues: a water leak or a problem with the head gasket. In the first case, this can occur from the thermostat, water pump, or radiator. Hoses rarely break, at least recently. Thermostats are made of plastic, which can degrade over time due to heat and cold; the water pump has a bearing with a seal that also deteriorates over time, leading to leaks. The pump is located within the timing belt, so if it is fully opened, it can cause significant damage. It is advisable to replace the pump when performing a timing belt change, as it is a major job, and if the pump fails, it will need to be done again. The radiator may have micro-leaks; the two caps are plastic and can also wear out, especially as they come into contact with the metal of the radiator, which tends to develop small cuts over time, leading to leaks. Now, let’s consider the issue with the head gasket. Recently, gaskets are made from three metals, making them less likely to burn, but you might still notice oil spots in the reservoir, indicating the head gasket has failed. Another method is to fill the reservoir to the brim, open the cap, and start the vehicle. If air bubbles emerge, the head is burnt. In that case, you risk causing serious damage if you don’t address it immediately.

Updated on 29 June 2026 by ScegliAuto

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