If you view coolant leaking under your vehicle or smell coolant from her car, you may need to change the heater bypass tube.

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The heater bypass pipe is a cooling system component found on numerous road going cars and trucks. It’s function is to serve as a cooling device passage the bypasses the thermostat, so that there is coolant flow also when the engine thermostat is closed. The coolant bypass tube offers a passage for minimum coolant flow, so that the engine does not overheat from insufficient cooling once the thermostat is closed and restricting coolant flow.

While servicing the bypass pipe is no generally thought about routine maintenance, the is still susceptible to the same worries that all cooling system contents are vulnerable to, and also can periodically require attention. Generally a faulty heater bypass tube will create a couple of symptoms that can alert the driver of an issue.

Coolant smell

One symptom that an worry with heater bypass pipe is a coolant smell from the engine bay. Most heater bypass tubes use an o-ring or gasket come seal the bypass pipe to the engine. If the o-ring or gasket wear out or tear, coolant will start to leak native the bypass tube. This may produce a coolant odor from the vehicle’s engine bay. Some coolant bypass pipe are located near the optimal of the engine, and also as a an outcome may develop a coolant smell far before any type of coolant deserve to be visibly detected without opening the hood.

Coolant leak

The most common symptom of an concern with the heater bypass tube is a coolant leak. If the bypass pipe gasket or o-ring become damaged, or the bypass pipe leaks because of excessive corrosion it may reason a coolant leak. Depending upon the severity of the leak, coolant may or no leak ~ above the floor or under the vehicle. A faulty gasket or o-ring might require a an easy replacement the the seal, when a corroded tube will certainly usually call for replacement.

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As the coolant bypass pipe is a component of the engine’s cooling system, that failure have the right to lead to engine overheating and potential significant engine damage. If her vehicle’s bypass tube is leaking, or has an additional issue, have actually the automobile inspected through a professional technician, such together one native usmam.org, to identify if the bypass tube calls for replacement.