Head gasket

The final point, you have to rule out, is the so called broken head gasket.

A broken head gasket means basically that the seal between the cylinder head and cylinder block is broken. The sealing between these two parts is done by the head gasket. The term broken head gasket is a general naming for a problem that can be even more serious than just a worn out gasket. It can very well mean that one of the cylinders is ruptured on the inside.

A car with a broken head gasket can still be driven. That is why it is so important that you check the engine before the purchase. Especially if you buy it without any guarantees! A broken head gasket or a cylinder block in a poor condition are recognized easiest after a thorough test drive. The hot fumes that are released in the cylinders during the combustion process will in this case not be directed completely via the exhaust system. If the gasket or cylinder is broken the fumes penetrate into the coolant, that will overheat. The result can be seen under the bonnet around the coolant reservoir. During the test drive the coolant will reach its boiling point and will be released via the pressure valve and splash over the parts around the reservoir. When you leave the engine running you can see the coolant boil in its reservoir.

Although the head gasket is not cheap to replace, in the end you will have a working engine. The real problem is the chance of a ruptured cylinder. If this is the case the whole engine will have to be replaced and this is most definitely an expensive repair.

Mind that the engine gets hot during the test drive! Watch out that you do not burn yourself while touching various parts. You can take your time between the test drive and the check.