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We go through some symptoms to help diagnose whether you have a cracked engine block or blown head gasket. Follow these steps to help point you in the right direction


Antifreeze In Oil

Coolant in Oil

 Just like a cracked engine block allowing engine oil to mix with the antifreeze, the opposite can also happen. Antifreeze can mix with circulating engine oil this only happens when an engine block has a deep enough crack, allowing the antifreeze to pass into the engine oils passageways. Usually when antifreeze is contaminated with oil an odour will be produced with a visible smoke exiting the exhaust, or a cloudy milky-coloured oil that can be spotted on the engine's dipstick.



Oil In Antifreeze

Oil in Coolant

 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. The engine block has small channels where oil and coolant pass through and circulate a vehicle's engine. If a cylinder crack happens close enough to these channels, passing engine oil can mix with and pollute circulating antifreeze. Fortunately checking this is easily done by removing the radiator cap and inspecting.


Low Engine Compression

compression test


Engine compression is the result of engine combustion; the combustion is housed within the engine cylinders which are located within the engine block. A crack in the engine block can be the cause of low compression. This will cause engine combustion pressure to be disrupted, lowering the engine compression causing poor engine performance.



Engine Smoke

engine smoke

Engine smoke is a major sign of a cracked engine block. Smoke from an engine is normally caused by a severely cracked engine block. This is often a sign of a severe engine block crack or fracture, normally coinciding with severe engine performance issues in addition to visible smoke.



Visual Crack in Block

crack in engine blockA routine visual vehicle inspection can sometimes be enough to fine a cracked engine block. If your engine is clean and free from excess dirt or grime a visual inspection could be enough to spot a problem these should be noticed when a service or possibly M.O.T is taking place. More often than not large engine block cracks cause obvious symptoms, but in some situations where there are no mechanical symptoms but you suspect a problem. Ask for it to be checked during routine maintenance or servicing.


Engine Overheating

Engine Overheating

Engine overheating will occur when a cracked engine block is severe enough to allow engine antifreeze to leak, this will cause the engine temperature to rise and in turn cause the engine to overheat. Engine antifreeze travels within an engine block around the combustion chambers. Only severe engine block cracks, or cracks that are deep inside the engine expose the passageways where the antifreeze circulates would cause the engine to overheat.



Checklist For A Blown Engine Block:

• Check your oil and antifreeze. If you think there is any discolouration or changes to either have then tested.
• Check if your engine is leaking oil or coolant. This will cause your engine to overheat quickly.
• Check for codes flashing on the dashboard. This is often happens with reduced performance or a noticeable change in the way the car feels while driving.
• Check the level of fluid in the radiator. If your car suddenly loses coolant or the level is very low this can be a sign of a cracked block.
• React quickly if you notice excessive smoke coming out of the exhaust.
• Check the radiator’s mixture of coolant, antifreeze and water to see if it has frozen.
• Check to see if the engine has overheated. Overheating can be caused by another engine problem, usually the head gasket but the overheating can be a cracked block.

Need to fix a cracked cylinder head but don't want to spend too much?

Use Steel Seal to repair a cracked block or head gasket; you don't need to know which is the exact problem within the engine as Steel Seal can repair most problems within the head gasket and cylinder head, or even both.


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Why Steel Seal?

Because Steel Seal simply repairs blown head gaskets, cracked blocks and warped heads and comes with a Lifetime Money Back Guarantee for when in the unlikely event it fails to do so.


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