Oil coolers are not new technology but it is relatively new to see them on so many cars!
Why do I have an oil cooler?
Oil cooler first turned up on early performance vehicles. Oil is designed to work in a certain temperature range. For example, if your oil is too cold it won’t lubricate your engine properly. That is why it’s important to keep your RPMs low when you first start your engine. Similarly, if your oil gets too hot it will breakdown causing a similar lack in lubrication. Also, extremely hot oil will burn to the inside of your engine possibly blocking oil flow to essential components.
Just like anything in your car that has fluid in it leaks are certainly possible. Your oil cooler is basically a small radiator that uses your engine coolant to keep your oil from getting too hot. That means it has both oil and coolant flowing through it so it has twice the opportunity for a leak. Oil coolers rarely crack so usually the only chance for a coolant leak is a cracked or broken coolant hose.
On the other hand, an oil leak can come from the gasket between the oil cooler and the block, or the oil cooler and the oil filter if your engine is designed that way.
Why do oil cooler gaskets leak?
- Accidental loosening
As you can see in the video above, these oil cooler gaskets compressor over time allowing oil to start seeping by. In the case of this Subaru, the situation was dangerous because the oil was dripping onto the hot exhaust which caused smoke and possibly a fire.
If your oil cooler is where your oil filter screws on, the constant removal of the oil filter can loosen the bolt holding the oil cooler on. The reduced clamping force on the oil cooler can allow the cooler to leak even if the gasket is still in good condition.
Lastly, like any gasket in your car, it can deteriorate over time. Excessive heat, dirty oil or vibrations can ruin your oil cooler gasket and cause leaks here as well.
As you can see in the video, replacing the oil cooler gasket is a pretty easy job as long as you can get to it. If you can avoid removing the coolant hoses you will save yourself a lot of time but if you do have to remove them, remember to burp your cooling system.
Remember to subscribe for more how-to videos!