Ask an expert
![P.McCracken](themes/aaAle/images/interface/profile-pic-placeholder.47cf740a.png)
hi could you please advise me on these questions, thank you for your time.
1. What are the typical signs of a blown head gasket, cracked head?
If a vehicle traveling on the open road doing speeds of 100km and over.
What would the symptoms of a blown head gasket, cracked head?
Would you expect, overheating, blue smoke? and steam from the radiator?
2. How far would you estimate traveling on the open road before these signs would become obvious?
3. If you had blown a head gasket, what damage could be done if you were driving it around trying to top up the fluids, would this crack the head?
4. Should the vehicle be driven if the head gasket is blown?
Thank you
Phillip
![Anon](/assets/aa/aa-avatar.png?m=1466990309)
Hi Philip,
There are a few different ways a head gasket can blow with both internal and external evidence.
Oil can leak externally from the head gasket and can be more of an annoyance that anything.
The most serious can occur if the vehicle ever overheats from either cooling system blockage (stuck thermostat or similar) or a loss of coolant due to failed component- if an engine is overheated enough a head gasket might blow and in some cases could crack, or the engine could get so hot it seizes.
Once a head gasket is blown, you could get engine oil passing into the cooling system and vise versa. You could also and most commonly get engine combustion gasses passing into the cooling system which then over pressurizes the cooling system and causes further overheating because of air in the cooling system and can also cause hoses to blow off or split.
How this is demonstrated to the driver would vary on the severity of the issue and symptoms could range from slight coolant usage over a week to a major overheat after only a few minutes of driving. Any overheated engine is compromised and at risk of further damage/issue later down the track- even if there are no symptoms immediately apparent.
![P.McCracken](themes/aaAle/images/interface/profile-pic-placeholder.47cf740a.png)
Hi Cade
What would happen if a vehicle was driven with no radiator fluid in the radiator , would it result in a cracked head ?
thank you
Phillip
![Anon](/assets/aa/aa-avatar.png?m=1466990309)
Hi Phillip,
It's hard to say what would and wouldn't crack a head- there are a few variables at play, engine design, head construction and placement (cast or aluminum etc.)
Some damage could even occur if cold water is added to a severely overheated engine.