If you are a car owner, nothing can ruin a day/mood faster than discovering you have a blown head gasket.
The second your trusted mechanic says those words, you immediately start to calculate the dent the labor and repair cost will do to your bank balance and the inconvenience it will cause you.
You immediately start thinking about what may have caused this problem, or what are the some of the symptoms of a blown head gasket that you may have ignored or missed.
If you haven’t figured it out yet, the head gasket plays an important part in the operation of your engine. It is the center between your cylinder head and engine block.
The main job of gaskets is to create compression so that your car can build up compression, while also sealing up engine oil and coolant from leaking by sealing the engine cylinders.
With that being said, here are some symptoms or signs to watch for to determine whether or not you have a failed gasket in your vehicle.
Most Common Symptoms of Blown Head Gasket
A bad head gasket is really among the worst car engine problems you can have. So how do you know if your car has a bad head gasket? Any of the symptoms below should indicate a problem that you need to check on with your mechanic.
#1. Bubbles in Your Radiator.
A bad head gasket can allow exhaust gases to leak into your antifreeze/coolant. If either of these conditions exists in your radiator, you will see bubbles that may appear to be boiling coolant. You can do a DIY blown head gasket check to determine if you have exhaust gases in your coolant.
#2. Loss of Engine Power.
When you suffer a head gasket failure that lets the compressed air/fuel mixture escape from your combustion chamber, you lose compression inside your engine’s cylinder. This leads to a significant loss of power in your engine.
While another issue may be causing the oil or coolant to leak, so there is a possibility that this might not mean your head gasket is blown, but it shouldn’t be ruled out until your mechanic checks your car.
#3. Dirty Spark Plugs.
While other engine problems can also leave some tiny whitish debris on your spark plugs you still want to entertain the idea of a blown head gasket.
The debris left on the spark plugs also occurs when the coolant is subjected to extreme heat inside the combustion chamber. Look near the electrode or ground strap of your spark plugs for these deposits.
#4. Car engine overheating.
While overheating of a car’s engine can be caused by various issues (such as a bad cooling fan or antifreeze leak), it could also be due to a blown head gasket.
Typically, this will occur from insufficient coolant leaking into the combustion chamber and turning into steam. If the condition is not diagnosed soon, this could create more serious engine issues such as warping or cracking of the cylinder head.
#5. Milky oil.
When antifreeze leaks into your car’s combustion chamber, some will seep into your engine oil. Then, when oil mixes with water, it will turn milky white over time.
Look at your dipstick and the underside of your oil cap for this mixture. Any coolant contaminating the oil compromises the lubricating properties, and only increases wear and tear on the bearings and cylinder walls.
#6. White exhaust smoke.
If your car is emitting white smoke from the exhaust, there is a good chance you have a HEAD GASKET BLOWN.
When coolant leaks into your vehicle’s combustion chamber, blistering heat converts flash into steam, and the steam flows out your tailpipe along with a sweet burning smell, and causes that white smoke.
#7. External head gasket leak.
This can be pretty straightforward when diagnosing blown head gaskets. A blown head gasket will occur internally where the gasket has failed between the outside of the engine and oil or water passageworks, which will allow a leak of oil or coolant from.
Everyone should start to look where coolant is leaking from these two gaskets slack steel – just below to intake or exhaust manifold, especially when the car is fully warm.
Seeing a leak should be very easy when there is no adjacent other cooling passages in close proximity to your head gaskets.
If there are other cooling hoses next to your head gasket, then you can consider adding an ultraviolet (UV) dye to the antifreeze/coolant, and then use UV light when trying to assess a head gasket leak.
Many car users are frequently asked, “Can you drive with a blown head gasket?” Well, no one wants to drive your vehicle if you are getting one or more of the above symptoms.
Just remember that the cold coolant leaking side and the hot gases leaking from the gasket can further damage the engine block or even crack, or warp the metal head.
What Causes a Head Gasket to Blow?
After a blown head gasket, next thing to do is figure out what the actual cause is prior to any head gasket repair or replacement. If you simply put another gasket in without addressing the issue, it will be blown again. So what causes a blown head gasket?
#1. Poor Installation.
In this situation, poor installation may be due to loose head bolts or not tightening to the most appropriate torque.
Other errors that could occur here are reusing old/used head bolts, and not using the proper torque sequence, as well as improper cleaning of the block surface or using one or more compromised head bolts.
Any of these factors, singly or in combination, could be an integrity issue with your head gasket.
#2. Overheating.
Overheating is the most common reason that creates damage to a head gasket. It can create extreme temperatures for the gasket. In erosion, the engine block and engine head expand. However, the head gasket must compress due to the collision of the engine facing function of the block (thermal barrier) and head expansion.
The expansion gap (tension) that is created in that moment destroys the seal, thereby causing the loss of compression to blow compression and/or leaking.
You’ll need to troubleshoot why your engine is overheating and make a fix prior to installing the damaged gasket. Some potential reasons are: clogged radiator, faulty radiator fan, leaking coolant, and others.
#3. Pre-ignition and Detonation Issues.
When combustion occurs normally, the flame that ignites the air/fuel mixture in your vehicles combustion chamber is delivered evenly and continuously.
However, when the octane rating in the fuel quality is low, the mixture is lean, and the combustion chamber is too hot, normal combustion may take place and lead to an abnormal combustion process such as pre-ignition or detonation.
#4. Detonation.
This happens when the ignition event in the cylinder occurs at a slow rate, letting pressure build-up that creates a second ignition location that produces a compression collision with original ignition.
The loud knock noise from the collision produces an internal vibration that can damage your gasket. Some of the causes of detonation include low octane fuel, advanced ignition timing, the poor distribution of fuel in the cylinder, etc.
#5. Pre-ignition.
In contrast, pre-ignition happens ahead of the spark plug firing sequence. This allows for two combustion sites evolving quickly enough, colliding to generate a ping.
Generally, pre-ignition is caused by the cooling system, carbon build up and / or an overheating exhaust valve, etc.
#6. Hot Spots.
Remember, some engines suffer from hot spots, particularly on the cylinder head and middle cylinders. Aftermarket gaskets are developed for these engines to better protect the head gasket from damage.
Furthermore, if you replace your old OEM gasket with incorrect gasket, it could cause a blown head gasket.
How do you Fix a Blown Head Gasket?
If you spot the signs of a bad head gasket, never ignore them. Unattended, these signs will result in damage to your exhaust system, fuel injection system or the engine itself could fail entirely.
After noticing system of a malfunctioning head gasket the best course of action is to immediately stop driving, have the car towed to your local mechanic and have them diagnose the presenting cause. Finally, here are a few possible options you may wish to consider.
#1. Using a Gasket Sealant.
Should you happen to see any signs of head gasket failure, you must act quickly. If you leave these issues ignored, could severely damage your exhaust system, fuel injection system or lead to engine failure.
Once you see these signs of an invalid head gasket, the best thing you can do is stop driving, have it towed to your mechanic or whatever local shop you trust and having them diagnose the original issue. Finally, here are some of the possible options you may want to consider.
#2. Replacing a Blown Head Gasket.
If your vehicle has a major leak, a head gasket sealer may no longer be effective. Therefore, the best choice is to find a trusted mechanic who can assist you to install a completely new gasket.
You want to be fast if this is the case; more damage typically occurs if you delay. However, it will cost you a fair amount of money to pay for the cost of installation, if you do not have the relevant mechanical ability.
After you have decided to replace your head gasket, dump the engine oil and the antifreeze by doing a radiator flush. A flush removes rust and sediment in the cooling system and lets you put clean antifreeze in when you are done.
Once you remove the top part, you can see how bad the damage is to the old head gasket, clean the surfaces, and prepare the surfaces for the new head gasket. Finally, make sure to keep all the small pieces you take off in a clean and safe location.
How to Prevent Blown Head Gasket?
By now you should know the different ways to blow your head gasket. If you have gone through this, you know, it is not a fun experience by any means!
The cost of the head gasket is not necessarily too significant financially, but the repair work can be fairly dreadful in terms of difficulty. Of course the trick to not having to replace the head gasket is know the usual causes of blown gaskets and how to prevent them.
Don’t wait until you notice problems with your car, as it is likely already too late. Always check for leaks if you are looking under the hood – such as when checking your car’s oil level. A good underhold work light will help with visibility.
Also make sure the coolant level is appropriate and the thermostat opens properly before driving away.
In the previous paragraphs, we mentioned that overheating is usually the primary cause for blow gaskets.
Obviously there are various limitations that lead to your car overheating – some include a bad radiator hose, too loose serpentine belt, debris in the radiator, failing EGR system, radiator fan failure, or a bad radiator cap, just to name a few.
The only way to prevent your engine from overheating is to keep and perform proper maintenance on your cars cooling system. But you can also take note of your car’s temperature gauge while driving. Don’t ignore the signs of a hot engine.
Hotspots are another potential cause for damage to your head gasket – especially if the car is older as the spaces between the central cylinders and the cylinder head are hotspots, and where modern automotive manufacturers reinforce their engines to avoid any potential head gasket failure.
Fortunately, you can replace your old head gasket with them modern multi-layered replacement gaskets that are available.
When it comes to installation, you better make sure to do it right or if you are not an experienced do it yourself’er should probably have it installed professionally.
In a vehicle head gasket installation, avoid using old or damaged bolts, since their stability and hold-down clamping force will likely be compromised at the original installation stage.
You should also consult your mechanic for any potential detonation/pre-ignition problems, and follow you vehicle manufacturer’s recommended oil/coolant.
Final Thoughts
Considering all the issues an impaired head gasket can cause to your car and engine, we can say you need to be quite pro-active; once you see any of the highlighted symptoms of the blown head gasket, you need to act fast, to prevent spending a lot of money repairing your vehicle.
Whenever going for a long distance drive, always check coolant levels, and never put a fully heated engine under any stress, which could lead to overheating and blown head gasket.
When looking for a mechanic to do any work on your car, ensure the mechanic thoroughly examines the engine and car and checks for any signs of leaks, made worse when under high pressure.