Denton Auto Repair

Coolant does not just vanish. If the reservoir keeps dropping, the system is either leaking externally, venting under pressure, or losing fluid internally, where drips do not reach the ground. Sorting those paths quickly protects the water pump, head gasket, heater core, and catalytic converter from heat and contamination. Why Coolant Disappears Without a Visible Leak Coolant expands when hot and contracts as it cools. The radiator cap manages that pressure and vacuum, sending fluid to the reservoir and pulling it back later. Any fault that lets air in on cooldown leaves the reservoir low even if the ground looks dry. Small leaks also evaporate on hot surfaces, so evidence can be faint or invisible by morning. External Leaks That Evaporate Before You See Them Plastic radiators often seep at the tank crimp seams and upper neck. Thermostat housings and quick-connects can mist a small ring around their fittings. Water pump weep holes leave a dusty tr ... read more