Skip the auto shop - Our mechanics make house calls

How Long Does a Radiator Drain Cock Last?

Radiator Drain Cock

Your car’s coolant system is one of the most critical on the entire vehicle. Without it, the engine would quickly overheat, causing devastating damage. Coolant is cycled from the radiator, through the hoses, past the thermostat, and around the engine. While it cycles, it absorbs heat, and then transports it back to the radiator, where it is dissipated with moving air.

Coolant is designed to absorb heat and also withstand freezing temperatures. This is what allows you to run your engine during the winter, when regular water would freeze solid. However, coolant has a finite lifespan and you should have it drained and filled once every five years or so.

Obviously, there has to be a way to get the old coolant out of the system before you can add new coolant. That’s what the radiator drain cock does. It’s a small plastic plug located at the bottom of the radiator. It screws into the radiator’s base, and allows the coolant to be drained out. Once the old coolant is out, the drain cock is replaced and new coolant is added.

The problem here is that the drain cock is made of plastic, which is pretty easy to damage if you’re not careful threading it back in. Once the threads are stripped, the drain cock will no longer seat correctly and coolant can leak out. If the threads are badly stripped, it’s possible that the drain cock will fail completely and coolant will be allowed to flow out unchecked (particularly when the engine is hot and the radiator is pressurized). Another potential issue is if the rubber gasket on the tip of the plug is damaged (this will allow coolant to leak out).

There’s no set lifespan for a radiator drain cock, but it definitely won’t last forever. With the right care, it should last for the life of the radiator (8 to 10 years). However, it takes very little to damage it.

Because a damaged radiator drain cock is potentially very serious, you need to know the signs of failure or damage. These include:

  • Threads on the drain cock are smoothed out (stripped)
  • Head of the drain cock is damaged (making it difficult to remove)
  • Plastic is cracked from heat exposure
  • Coolant leaks under the radiator area of the car (can also indicate a leak at a hose, from the radiator itself and other areas).

Don’t leave things to chance. If you suspect your radiator drain cock is damaged or have a coolant leak, a certified mechanic can help inspect the radiator and drain cock, and replace any parts needed.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

How to Transfer a Car Title in Idaho
In order to prove ownership of a car, you must have the title. However, when a car is sold, given away or inherited, the title needs...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
P2159 OBD-II Trouble Code: Vehicle Speed Sensor B Range/Performance
Diagnostic Trouble Code (DTC): P2159 P2159 code definition Vehicle Speed Sensor B Range/Performance...


Related questions

Q: Is it a blown head gasket?

Hello. If it leak shows up after 20 minutes of the vehicle running even after you put the k seal in you will still have to replace the radiator because the k seal isn't properly doing its job in fixing...

Q: Overheating problems.

The radiator may have partial blockage that will cause the overheating after you put a load on the engine from driving. Have the radiator checked with a temperature probe to see if parts of the radiator has blocked passages. If...

Q: A little oil in radiator?

Since you have a manual transmission, there are no transmission oils going into a cooler in the radiator. The only way coolant and oil can mix is from the engine oil getting into the coolant passing in the engine. This...