Can someone explain the primary job of a head gasket in a car...? and also why when fixing a blown one it takes of chance of blowing again? To further explain I took my mini van into the shop for its usualy tuneup and also because my heat wasnt working an was told that my head gasket was blown an that it may be better to buy a new car than to fix mine because it could start knocking again in a few months. So I am curious as to why would a repaired or new gasket run this risk?? I am a female who knows little about cars and I just need some insight an info so I can make a decision to have the car repaired or buy another

< class="additional-details">Additional Details 17 hours ago Yes I trust my mechanic he has been a very long time friend and also my mechanic an only person I trust with my vehicle for years. The problem is I just plain didnt understand what the problem was. The head gasket is the seal between the head and the block of the car. There are many oil and water channels in there, so it's bad if it leaks.

Head gaskets usually blow if your car is overheating and the head warps from the heat (it's usually made of aluminum). When you replace a head gasket, it's important to make sure the head isn't warped, which will cause it to fail again. Many times, you can resurface (deck) the face of the head to make it flat.