Symptoms of a Bad or Failing Radiator Drain Cock

The radiator drain cock is located on the radiator of modern vehicles. Its job is to make draining the radiator much easier and the radiator fluid serviceable. It is located underneath the radiator and can be spotted by the winged threaded bolt. Older vehicles do not have a radiator drain cock. Instead, to replace the fluid in the radiator on these vehicles the fluid must be drained by removing a radiator hose which can be time consuming and messy. The radiator drain cock in modern vehicles makes it easy for mechanics to drain and replace radiator fluid and saves customers time and money on repairs. However, this part does come with some potential for issues.

Over time, the radiator drain cock can become damaged, leak, and fail. The following are a few symptoms to watch for if you suspect you have a failing radiator drain cock:

1. Leaking coolant

Since the function of the radiator drain cock is to keep coolant in the radiator, any leaking coolant should be a red flag that the drain cock is not working properly. The fluid is normally green in color and has a sweet smell to it. As soon as you notice leaking coolant, contact a professional mechanic to have your radiator drain cock inspected and replaced. It should be noted that leaking coolant can be a symptom of a leaking radiator, so it is best to have a mechanic inspect the entire coolant system.

2. Leaking around the drain cock

If you suspect there is a leak and you are able to physically inspect the drain cock, check to see if there is leaking coolant around the radiator drain cock. In many cases the radiator drain cock is plastic and can fail due to heat and age over time. There should be no fluid in this area if the drain cock is working properly.

3. Threads are stripped

If you are able to get underneath your vehicle and inspect the radiator drain cock, check to see what condition the threads are in. If the threads are stripped, you will need a new radiator drain cock. Radiator drain cocks are most often plastic and are easy to over tighten and strip. This should be replaced by a mechanic to ensure the entire coolant system is sealed without air in the system and working properly.

A leak in the radiator drain cock should not be left for too long as it is a vital part of your vehicle’s cooling system. YourMechanic makes getting repairs to your radiator drain cock easy by coming to your home or office to diagnose or fix issues. You can book a service online 24/7. YourMechanic’s qualified technicians are also available for any questions that may arise.


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