This section is to provide assistance troubleshooting the problems you are having with your engine and specifically your cylinder head. Simply replacing a warped or cracked cylinder head does not fix the original problem. If you do not find and fix the original problem that caused your cylinder head to fail then it will happen again. This page will discuss some of the more common problems that cause cylinder head damage and more importantly some of the steps you need to take to avoid these problems in the future.
If an engine overheats, it can cause head gasket failures and cracked cylinder heads. Generally, the operating temperature of an engine should be between 190-220 degrees. Temperatures in excess of this will put stresses on the cylinder head and engine block. The stresses from overheating cause these parts to expand beyond the engines tolerances. This will lead to a blown head gasket and/or a warped or cracked cylinder head.
Common causes of overheating:
Low coolant level or coolant loss – Always maintain your coolant level per the manufacturers recommendation. Continued loss of coolant may indicate external leaks around hoses, gaskets, radiator, water pump, thermostat, heater or freeze plugs. A cracked cylinder head will also cause coolant loss and is sometimes indicated by white, puffy smoke coming out of the tailpipe.
Air Pockets in the Cooling System – Occasionally coolant is drained from the engine to make repairs or as part of your general maintenance. Air pockets may form when coolant is refilled. If the air pockets are not bled out of the cooling system prior to startup, the air pockets will cause the engine to overheat. Always follow the manufacturer’s procedures when refilling your cooling system. Many vehicles have bleeder holes or valves that allow you to remove the air pockets.
Faulty Thermostat - If the thermostat is not opening and closing at the correct temperature, it will cause your engine to overheat.
The radiator, water pump and clutch fan should be maintained per the manufacturer’s specification to avoid overheating.
This occurs when temperatures inside the combustion chamber get so hot that the fuel will ignite without a spark from the spark plug. Preignition will cause the vehicle to misfire, run poorly and eventually burn the valves. Common causes of Preignition are improperly operating EGR, mistimed engine, wrong fuel/air mixture and vacuum leaks.