Technical > Automotive > [Help] Mechanic says I have a blown head gasket?

[Help] Mechanic says I have a blown head gasket?

It depends on the design of the radiator reservoir. I believe one of the designs involves the radiator filling after the engine is shutdown through a suction action created when the car cools. I would say if you are losing fluid like that your mechanic is right.

reply to becdetmer
The cap must be lined up on it arrows or the overflow tank will not refill the radiator. Anytime an engine runs hot and the overflow is found empty then the radiator level needs to be checked by removing the cap when the engine is cold to visually make sure that it is not empty as well. Not checking the actual radiator level after overheating can cause it to overheat again damaging the engine, blowing the head gaskets and possibly cracking the metal in the heads due to the lack of coolant in the system. When the system is really low, there is not enough coolant to cover the temp sensor and the engine will overheat, lose power, but the dash temp gauge will not show overheating until after the damage is done.

There is not a quick fix to blown head gaskets as it is labor intensive work and requires that the heads be sent out to a machine shop for cleaning, visual inspection for surface cracks (which means new or used heads to replace the cracked heads if found to be in that condition) and/or being warped/twisted from the overheating which would require the head surface to be refinished (machined flat again on a table lathe or flat table) so that it is true and flat again or the new gaskets will not seal properly which will lead them to fail again prematurely.

Sometimes and it is only a "bandaid" at best, you can seal slight head gasket leaks with a product called Bar's Leaks. However, the directions are time consuming and must be followed exactly or it will not work for even a minute. All coolant has to be completely flushed from the engine and only plain water can be used to treat the leak areas with the sealer. Once treated and left to air dry for 6-12 hours after draining, then and only then can coolant be put back in the engine since coolant being slick prevents the sealer from working but the coolant does not affect the sealed area after it has air dried as it has changed chemistry when hardened when applied properly using water alone. Read product bottle for exact steps.

reply to becdetmer

reply to Doctor Olds
Doc, Why am I having Dejavu »www2.dslreports.com/forum/r19411···nic-Woes

Too coincidental.... One appears to be from the husband, the other from the wife.

Sadly it sounds like their lack of meeting the vehicles basic maintenance needs (coolant flush and fill plus cooling system diagnostic test under $60.00) has cost them a whole lot more. Perhaps their next vehicle will receive its needed attention before instead of after the fact if they learn from this very expensive mistake.

I've seen too many vehicles killed like this over the Years and it is from the I'll drive just a bit further cause I'm late or I don't want to walk let's keep going excuses being just enough to fry the engine good. That and the it doesn't need looking at now as it cooled down and I topped off/refilled the overflow tank so it can't overheat again attitude.
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What’s the point of owning a supercar if you can’t scare yourself stupid from time to time?

reply to becdetmer
I would check/replace the thermostat. Without out knowing how quickly the fluid leaked out to begin with, hard to say if/how bad the leak is. If you replace it and still have overheating problems, it may get expensive as stated above. Until you do it yourself, it is hard to imagine a $30 part costing $1800 to put in.....
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No, I'm not a technician. But I did stay at a Holiday Inn Express last night.

They are way past putting a T-Stat in as the engine is now physically damaged from lack of coolant and being driven too far while overheated. There is one thing you never do is continue to drive an overheated engine as each 1/4 mile (.25 mile) just creates a ever increasing repair bill that easily could have been prevented. I've seen then driven so hot it destroys the auto transmission also.

Regards,

Doctor Olds
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What’s the point of owning a supercar if you can’t scare yourself stupid from time to time?

reply to becdetmer
Smores anyone?