Can someone explain a damaged head gasket

I have a damaged head gasket, so that means there is a breah in the gasket that is allowing air to escape because I am getting air up into my radiator overflow. This happened before I bought the car and believe it happened via overheating. So my questions are:

1. With the breach, how come antifreeze is not getting into the engine? If air is able to get out how doesn’t antifreeze not go into that same breach?

2. I have read about a product called steel seal which supposedly will seal up small breaches in a head gasket. Since it is mixed in with the antifreeze how in the world can it fill the breech?

3. If you have a breach in the headgasket, should your engine run rough or sound wierd?

If you’re getting air in the cooling system from a breached head gasket, it indicates one of the fire rings on the head gasket has failed and is allowing air to be pumped into an ajoining water jacket from a cylinder. A head gasket can fail in this area where once the piston stops moving, the pressure from the cooling system tries to push coolant back towards the cylinder. If the head gasket has failed where pieces of the head gasket get pushed together under this reverse pressure, it can create a dam where it allows little or no coolant into the cylinder.

Steel Seal is just sodium silicate. Sodium silicate and antifreeze both readily mix in water and are compatible. As a matter of fact, some antifreezes still contain silicates.


You may be getting some coolant drawn into the engine and blown out with the exhaust as steam. It may be too small a cloud for you to see.

The head gasket provides a seal around the combustion chamber between the cylinders and the water jacket in the place between the block and the head. It also provides seals around the oil passages that go from the oil channels to the valve train and back, and seals all of these things from the outside world.

When you get a breech, it typically occurs between a cylinder and the water jacket. That’s because the seal that surrounds the combustion chamber is subjected to millions of explosions, very high pressure spikes at temperatures sometimes upwards of 2000 degrees F. That’s where it typically blows out. Those areas are surrounded by the water jacket. Exhaust gasses at very high pressures will blow through the breech every time the cylinder fires. At 3,000 RPM, that,s 1,500 times every minute, 90,000 time per hour. Those gasses are what create the bubbles, which then migrate up to the system’s highest point…the radiator cap. The heat from those exhaust gasses also can overcome the ability of the cooling system to dissipate it, and the engine overheats.

Coolant can be pulled into the combustion cylinders through a breech with each intake stroke. That’s when the cylinder creates a vacuum, the same one that pulls air and fuel into it. But the vacuum forces are no where near as strong as the combustion forces, and gasses go through the hole much more readily than coolant does, so the amount of coolant that gets drawn into the cylinders will not match in volume the amount of combustion gas that gets blown into the water jacket.

Overheating can warp the head and make the seals created by the headgasket less effective, exascerbating the problem. The headgasket relys on the two surfaces between which it’s sandwiched as bothe being flat.

It’s difficult to explain. I hope I’ve helped.

I don’t know how or how well steel seal works. If this Taurus is an old beater, IMHO it’s worth a try. If the car is otherwise a good car, I’d consider getting it repaired properly.

Tester and I were apparently writing simultaneously. The “fire ring” he’s referring to is a metal ring around the cylinder hole that’s part of the headgasket. It’s necessary to enable the gasket to withstand the high prssures and temperatures.

His comment about the break acting like a one-way “check valve” is a good point. I missed that point.

Wow, it is nice to finally find out what I have. I mean I know I have a bad head gasket, and what a head gasket is, but could not get any info on exactly how it all happens. Mine is a beater ($450 at auction) so I am looking at giving steel seal a shot as I figure if it just addes say a year to the engine I come out way ahead. There is a place here in Indy that does it for $150, so I plan on getting it done after I get the other ball joint replaced ($120 dollars).

Is this the same $450 Taurus that was in a previous thread?

The coolant only has 14 psi pressure behind it…Combustion pressure has over 1000 psi behind it…Blown head gaskets are a NEVER ENDING problem with MANY engine designs. This has been going on for 70 years…When blown head gaskets simply CAN NOT be tolerated, as in racing and aircraft engines, the head and cylinder are made in ONE PIECE so there is no head gasket to blow…

yes, in many previous posts.

Yes, do the ball joint first. It can kill you whereas the head gasket most likely can only kill the engine.

However, if you are going to drive around with a known bad head gasket, it might be a good idea to remove the radiator cap every morning when the car is cool and check the coolant level. Most likely your leak will get worse over time. Whenever the engine cools off after being driven, coolant will likely be sucked through the leak into the cylinder. It’ll get burned off when the car is started again, but you probably won’t be able to see the cloud of white smoke at start up from the driver’s seat unless the leak is really bad.

What you are concerned about is making sure that you don’t leak off so much coolant over time that the car overheats. I suspect that burning coolant isn’t great for the engine as cylinders that have been doing so are shiny clean – which probably means that the rings are not getting enough oil. But like you say, it’s a beater.