I removed the left head and the shop found 2 cracks, should I go ahead and replace both heads or just the known bad one?
The machine shop said the left head had 2 large cracks probably caused by overheating. Should I just replace this head (it was leaking exaust and fluid and was the reason for taking it to the shop) or is the other head probably cracked too and I should just go ahead and replace both?
My car has 115000 miles.
My car has a manual transmission.
Experienced mechanics share their insights in answering this question :
I would recommend removing the other head and inspecting it for cracks also. I would recommend having the head overhauled, and if needed, replacing it then. If you can get them cheap enough, I would suggest replacing both heads if possible.
How to Identify and Fix Common car Problems ?
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If the head gasket fails between a coolant channel and one of your engine`s combustion chambers, the engine may start to consume coolant. This can lead to the engine overheating, too, due to an insufficient coolant level.
If it`s still overheating after a head gasket replacement, there`s a good chance that the engine has suffered damage. This may be better than it sounds, as components like a damaged thermostat could be to blame. But it could also mean that the engine block itself has become cracked or slightly warped.
Signs of a blown head gasket in a diesel tractor
An increased engine running temperature. Engine gauge showing maximum temperature after a few minutes. A cloud of exhaust fumes when idling, or white smoke coming from the exhaust. Coolant clearly leaking onto the ground beneath the head gasket.
Compression leak to coolant: If you are seeing low engine coolant levels, or a sweet-smelling white smoke coming out of your exhaust, the head gasket may have blown between the cylinder and coolant passage. A drop in coolant levels or exhaust gasses pressurizing the cooling system can cause the engine to overheat.
When they blow, intake manifold gaskets and head gaskets will typically leak different substances. A blown intake manifold gasket may cause air or fuel to leak. A blown head gasket, on the other hand, will typically cause combustion gases, coolant or oil to leak.
Over time, due to repeated exposure to high levels of heat that cause the gasket to expand and contract, the part can become cracked. This will allow fuel, air, and coolant to leak out of the engine, making it overheat.
Is it safe to drive with a blown head gasket? No, the sooner you get it fixed, the better. Aside from the damage it will do to your engine, driving with a blown head gasket can be dangerous.
A major sign of a cracked engine block or blown head gasket is when you can see the engine`s antifreeze has mixed with the oil. A cracked block or blown head gasket can cause the circulating engine antifreeze to mix with passing engine oil.
How long do head gaskets last? The answer is, they should last as long as the life of your engine. However, if you don`t properly maintain your vehicle or the engine, chances are you`ll be having the head gasket replaced in your vehicle`s lifetime.
Most engines will blow a head gasket when the coolant temperature has reached 260 degrees or more.
When idling, the engine relies on coolant water to cool it down. But a blown head gasket causes the coolant to flow into the engine block and get combusted. You`ll also notice that the coolant level drops and the engine overheats.
Another common symptom of a failing water pump is an overheating engine. If the water pump is not circulating coolant properly, it can cause the engine to overheat.
Non-Asbestos Sheet Material Gasket
Non-asbestos materials are considered the most reliable option for all sealing flanges and are used in various applications. As the name would suggest, non-asbestos sheet material gaskets are cut from sheet materials that do not contain asbestos.
While steel is the most common material in which head gaskets are made, other gaskets are made of rubber, silicone, cork, felt, nitrile, fiberglass and Teflon. Fiberglass is often preferred because of its ability to withstand excessive pressure.
Once the temperature of the coolant rises to between 180 and 195 F (82 – 91 C), the thermostat starts to open, allowing fluid to flow through the radiator.
A blown head gasket is a serious issue, as mechanical problems in the vehicle may have caused the problem and will need fixing. In addition, the head gasket problems may have caused engine failure or serious damage to the engine components, and that situation will need addressing.
If the blown head gasket is preventing your car from starting, it`s likely it`s because there is an opening in the engine, and it can`t build up the compression that`s needed to create a spark. A mechanic will be able to take a good look at your engine and diagnose the issue.
Combustion temperatures and torque-producing cylinder pressures are always at work trying to force the cylinder head and block connection apart. If the temperatures or pressure spikes in the engine are too much for the head gasket to contain, the head-to-block connection will fail.
“A head gasket serves as a seal between the engine block and cylinder head, preventing engine fluid leaks and pressure losses.”
When idling, the engine relies on coolant water to cool it down. But a blown head gasket causes the coolant to flow into the engine block and get combusted. You`ll also notice that the coolant level drops and the engine overheats.
When idling, the engine relies on coolant water to cool it down. But a blown head gasket causes the coolant to flow into the engine block and get combusted. You`ll also notice that the coolant level drops and the engine overheats.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
I removed the left head and the shop found 2 cracks, should I go ahead and replace both heads or just the known bad one?
ANSWER : I would recommend removing the other head and inspecting it for cracks also. I would recommend having the head overhauled, and if needed, replacing it then. If you can get them cheap enough, I would suggest replacing both heads if possible.
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