Ford Thunderbird

How can you tell if you have a blown head or a blown head gasket on a ford 3.8?

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2015-07-15 18:26:24
2015-07-15 18:26:24

There are a few symptoms of a blown head gasket. The first one is loss of coolant. Coolant can be lost from the leak in the gasket into the cylinder. From there it can go past the piston rings and into the crankcase or it can be forced out of the exhaust system by the action of the piston coming up on the exhaust stroke.

If the coolant enters the crankcase it mixes with engine oil. Of course oil and water don't mix very well but the presence of ethylene glycol (anti freeze) and the agitation caused by the crankshaft and other moving parts can whip the mixture of coolant and oil into a milkshake.

If the coolant is forced out of the exhaust system it is usually heated by the hot exhaust manifold and the rest of the exhaust system. This results in a sweet smelling steam emanating from the tailpipe. The steam is rather persistent, that is it will hover in the air and not dissipate like the normal steam that comes from the combustion process.

Testing an automobile engine for a blown head gasket is pretty straightforward. The first check is to see if there are combustion gasses getting into the cooling system. Take a sample of the coolant and go to the local radiator shop and request that they analyze the coolant for the presence of hydrocarbons. If they are present then it is most likely that you have a blown head gasket.

Another check is to look at the oil of a warmed up engine. The antifreeze in the oil will whip it up into a frothy brown mixture that looks like a milk shake. If it looks like chocolate mousse then you probably have a blown head gasket.

Another check is to fill the cooling system to the brim and remove the radiator cap. Do this when the engine is cool. Start the engine and race it. If there is a compression leak and the gasses are going into the cooling jacket then the gasses will displace the coolant. Since the cap is off the coolant will be pushed out of the radiator. You probably have a blown head gasket.

One of the best ways to check is to hook up a compression tester, "this is a simple pressure gauge that screws in where your spark plugs go, you have to do each cylinder one at a time, remove a spark plug and screw in the tester, then crank the engine or start it and observe the reading on the gauge, compare this reading to the factory specifications wich can be found in the chiltons or alike book for your vehichle they can also be found online. If your reading is lower than the factory specs you most likely have a blown head gasket, and testing in this manner will also tell you wich cylinder. Although for repair one gasket usually covers 3-4 cylinders or one head.

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A compression test will tell you if a head gasket is blown on ANY engine. Also, white smoke tells you that your burning anti-freeze, which means a head gasket is blown.

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Just look at your engine oil and you can tell, if it looks milky there is water getting into the oil and that's the sign of a blown intake gasket or head gasket.

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A dye test will tell you if your head is damaged in the event of a blown head gasket. It turns colors anywhere it is leaking on the head, hence where any cracks would be.

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A compression test will verify if the head gasket if blown or not, the majority of the time.

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I hate to tell you this but I just paid $3,500 at the Nissan dealer for head gasket replacment.

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