Reader Question: I have a 1992 Mercury Topaz. I took it to the mechanic this morning because it was shaking when I stopped. He said the heat kept going on and off so I needed a head gasket and a new motor.
I would definitely get a second opinion before I did anything to this engine. These engines are notorious for head gasket problems due to overheating, but I would have a honest qualified mechanic do a cooling system pressure test, then an engine compression test FIRST to determine if there is internal engine damage. You need either a new head gasket or a new motor but you would not replace both.
Common signs of a blown head gasket or engine damage due to overheating are:
1. Engine overheating
2. Water in the engine oil – will look like a chocolate milkshake
3. Engine missing and running bad and poor performance
4. White smoke out the tailpipe
5. Coolant loss – constantly adding coolant to the radiator with no external leaks found
Here is an article about head gasket failure from overheating and an over the counter additive that I have had great success with repairing blown head gaskets.