Tag Archives: head gasket

Scrutinise the Cylinder Head Assembly

Scrutinise the Cylinder Head Assembly

Any mechanical failure must be analysed by an expert technician. They have a wide experience of working with machines and one should not be under the impression that by doing certain DIY tasks on weekends you can gain enough skill to perform a procedure of this scale. However, if you have taken the decision to do this job yourself then read on to know more about the process.

In order to provide the necessary lubrication the engine oil must flow through the ports that are present in the engine block and cylinder head assembly. Through these very ports engine coolant is also made to flow in order to control the temperature.

To prevent the fluids from mixing up and the compression from seeping from one cylinder into another, the cylinder head gasket is cut in a way that each cylinder is sealed and so are the respective oil ports and coolants.

Remember: The coolant turns into a brown sludge when oil enters the cooling system in a malfunctioning cylinder head gasket. You can notice this when the radiator cap is pulled off or when you take out the oil filler cap. However, there are other factors too that can trigger this possibility and in this article you can find the possible reasons behind such occurrences.

Step 1

Block Head - In Town Blog

‘Examine the engine block and cylinder head’

You should conduct a thorough examination of the mating surfaces of cylinder head and engine block to ensure that it is flat and uniform which is extremely crucial to maintaining a perfect seal.

Sending the cylinder head assembly to a machine shop will ensure that you get a professional cleaning and inspection. The technicians at a machine shop will advise you if a valve replacement is required. They will also give you instructions about the possible issues with the engine, things that you need to bring along and other such details of their services.

A good way to gauge the flatness of cylinder head and engine block mating surfaces is to use a machined straight edge. The necessary specifications and measurement limits can be found in the vehicle service manual. The mating surfaces of the cylinder head and engine block must be perfectly flat and straight throughout. If it is not this way then the component may have to be replaced.

The straight edge should be placed across the engine block deck. A simple test to see if the engine block needs servicing or not is to switch on the flashlight and flashing it onto one side. If you are able to see light by peeking between the straight edge tool and engine block then you need to service the engine block. It happens because the deck is not flat and uniform and light becomes visible between the spots that have warped.

Remember: The technicians at the machine shop are the best judge of whether a mating surface is as flat as it should be. It will incorrect to jump to the conclusion that head gasket needs to be replaced solely based on the above deduction. Hence it is advisable that you consult with a technician before going ahead with the procedure.

Step 2

Head Gasket

‘Clear out the engine block and cylinder head assembly’

The mating surfaces of the cylinder head assembly and engine block must be absolutely clean. The technicians at the machine shop, to which you take your cylinder head, will look after its servicing and cleaning.

If you intend to clean this component yourself then you shouldn’t forget to check the surface between the intake and exhaust manifold. If the head gasket has suffered extensive damage then there are high chances of the cylinder heads being harmed as well. However, it is not easy to fix this problem yourself as you will need special tools and the procedure is something not every DIYer can handle.

Remember: To clean these surfaces you should never make use of grinding wheel or revolving disc as they can cause erosion of the metal surface. Using such tools can cause small granules of metal to get deposited in corners where it can be difficult to remove them. If the dust falls around the pistons in the combustion chamber there are chances of scratches along the cylinder walls. Needless to say it is a process that needs to be handled with utmost care and for this reason we recommend getting this problem fixed at the hands of experts.

Step 3

Engine Bay - In Town Blog

‘Examine other components during dismantling’

It is not every day that you open the engine and take out components. Thus this is the best time to examine the components taken out while replacing the head gasket. By doing this you will be aware of the wear and tear that other components have been through and this should help you to prevent trouble in the future.

Remember: During the removal process there is high possibility of damaging spark plugs, coolant, belts, ignition wire, engine coolant thermostat, worn pulleys, timing components and seal. Also you may not have the different tools and components that are required for a particular procedure as it varies according to the application. Due to these complications, you should let a technician handle the head gasket replacement procedure who can do it at affordable rates.

Step 4

‘Clean the Threads’

The spiral grooves of fasteners and bolt holes are susceptible to dust collection and this can lead to building up of dust and rust which can affect their ability to fasten around. They can also result in inaccurate torque numbers which happens when the fastener get stuck on the dirt. You can take these fasteners and bolts to the nearest hardware store and get these replaced. Any dirt that has collected along the threads can be easily cleaned using a tap on the cylinder head bolt holes.

Remember: Engine blocks usually have studs that are installed in the block. After the cylinder head has been fixed on the studs, a cap nut is fitted. The manufacturers’ manual should contain details on how to handle the studs. The studs can need changing and replacement from time to time and the stud holes should be cleaned thoroughly.

If you have a doubt about anything mentioned then you should not hesitate to take assistance from a professional. It is easy to become stubborn during a DIY task and assume that you do not need any help, but in this process you may cause more damage than what already is.

Head Gasket Reassembly

Replacing a Faulty Head Gasket Part III: Head Gasket Reassembly

Do not think that opening the engine and fixing the head gasket is the end of the process. The other equally important part is to reassemble all the components that have been taken out during the process.

Step 1

Step 1 HGR

‘Spray the cylinder head gasket with a sealer’

Before you place the cylinder head gasket on top of the clean engine block you should spray both sides of the cylinder head gasket with a sealer. Also the studs should be installed before the gasket is fitted that is if studs have been used to hold the cylinder head down. Alignment dowels are often used with the studs to ensure that the gasket remains immobile while the cylinder head is being placed on top of it.

Remember: After installing a new cylinder head gasket, if you wish to make sure that the seal has been applied in a sturdy manner then you can make use of copper sealant sprays that are sold by many vendors. If you avoid the common maintenance mistakes you should be able to prevent problems from turning up in this corner of the automobile.

Step 2

‘Installing the cylinder head’

Once the surfaces have been cleaned and the gasket has been put in its rightful place you should install the cylinder head and fasten it down.

Remember: All information regarding the tightening sequence, the fastener torque and frequency of servicing can be found in the service manual. There is a particular pattern that needs to be followed during the reassembly, which is quite similar to the process of taking out components. It is also important to make sure that there is very little stress placed on the components and this can be achieved by ensuring that the sealing process is completed with absolute accuracy. You may also need several passes of increasing torque measurements in some cases. Use a calibrated torque wrench and stick to the procedure described in this blog.

Step 3

Step 3 HGR

‘Replace components that were removed in earlier steps’

You should have used notes and pictures to keep track of the components that were removed. When all components have been put back in their place take a brief look at the fasteners, components and assembly.

Remember: If any seal was disrupted during the dismantling process then it should be replaced and all the mating surfaces should be cleaned along with threads of bolt holes and grimy bolts. There are also some components that do not need sealing but require a gasket maker or silicone paste which is easily available at a local auto-parts store.

Step 4

‘Connect the battery and refill the fluids’

Before connecting the battery you should reassess all the work done. You should then proceed to fix the positive cable first and then the negative cable

Once you are assured that you have done the reassembly exactly how it should be you can refill the engine with oil. You shouldn’t forget to use a new filter and check the oil level in the engine.

Do not forget to fill the radiator with coolant oil to its optimum level and then wait. If you see some bubbling then it could be due to trapped air in the cooling system. Before starting the engine the cooling system has to be bled. If you want to make the air travel to the overflow tank or the highest point in the system then you should lift the front section of the vehicle. It is also advisable to check your coolant levels and make sure they are at optimum levels.

Caution: Installing the cables in reverse order can cause sparks and it can ignite any flammable liquid in the vicinity.

Step 5

‘Check for Faults’

This is the time to get into the car and turn on the engine. Do not start the vehicle at this point. If you have a code reader then now is the time you should attach it. If a component hasn’t been plugged in, the code will be fixed instantly. If a component has been left unplugged then you can trace it easily with the help of a code that may pop up at this time. Keep your ears alert at this point and use this guide to know what the noise could mean.

Step 6

Step 6 HGR

‘Set climate control’

At this point, you should start the vehicle and set the climate control to maximum heat. This makes the coolant enter the heater core and gives it the chance to get rid of any stubborn air bubbles inside the cooling system.

Remember: You should let the engine remain in idle state and allow it to match up to the temperature slowly instead of racing the engine. After the process is complete you should open the hood from time to time to ensure that there are no leaks or smoke coming out of the engine. You should also check the readings on the instrument cluster at regular intervals.

Dangers of DIY

Just like the information given above, there are many car websites on the internet that make this job sound easier than what it really is. Preferably you should leave such a complicated task to the experts as they know very well how to go about it.

For the sake of saving some money you should not risk trying a job of this big magnitude. There are several tests that need to be conducted before and after installing the head gasket and skilled technicians are well acquainted with these tests.

One needs to be completely sure that the head gasket needs replacement because once started it is quite difficult to get things back to the original state if you cannot handle the job well. Some people come to this conclusion that the head gasket needs to be replaced simply because the engine is getting overheated and white smoke is being emitted from the exhaust. However there are many other issues that can cause similar symptoms.

Therefore a series of tests is recommended to ascertain that the head gasket needs a replacement. If you replace the head gasket when there was no need to do it you not only waste a lot of money but also risk causing some damage to the engine. Moreover, repairing or replacing the gasket on your own can cause warping on cylinder and engine heads and if left untreated can lead to total engine failure shortly after repair.

Therefore, it is highly recommended that you take your vehicle to a reputed garage in your neighbourhood and let them test and solve the problems that you have been facing with your ride.

Replacing a Faulty Head Gasket

Replacing a Faulty Head Gasket Part I


One of the most vital parts of any vehicle’s engine is the head gasket. It seals the head of the cylinder which houses the valves of the engine to the engine block which has pistons and crankshafts inside.

The leaks in the head gasket can range in severity. Negligible leaks can simply make the engine guzzle extra oil or coolant. Severe leaks can lead to the mixing of coolant and oil which causes loss of lubrication in the crankcase or absolute loss of compression which leads to relentless issues with drivability.  A car that runs poorly without an obvious explanation is likely to have a blown head gasket and should be checked thoroughly for the problem. There are few symptoms that point towards a blown head gasket. Any car showing signs of these symptoms should be put through a compression test to check the reliability of the head gasket.

The head gasket of a car is a simple piece of metal that is enveloped in a rubber-like material and yet its malfunction is one of the most disabling ailments that an engine can face. To understand why this is a matter of concern, you first need to understand the vital role your head gasket plays in your engine’s health along with understanding the various car engine problems.

What is a head gasket?

The cylinder head gasket is the seal located between the engine block and cylinder head assembly. An in-line engine design contains one cylinder head as this is arranged directly along the engine block.

A “V” shaped engine design for instance, the V6 or V8 comprises of two cylinder-heads one for each bank.  A V6 engine has 3 cylinders located on each bank.

Note: An extensive amount of labour is involved with the repair of the cylinder head gasket even if the displacement engine is smaller in size.

Get a professional to establish if cylinder head gasket repair is required or not with the help of official testing. This repair is intensive in nature and cannot be simply done for any reason at all. At times, it can end up doing much harm than good if not done properly.

Word of Caution: Ensure that you always employ safety measures while working on your car to prevent any injury or hazard. Put on the recommended safety gear including gloves and safety glasses while handling engine oil, coolant and other components of the vehicle.

Getting to the Task of Replacing a Faulty Head Gasket


Before arriving on the conclusion that the task of replacing the gasket is the job best left to experienced professionals, you can make an effort to understand the reason why it is difficult to replace the head gasket on your own. This process requires major level of engine dismantling before you even get to touch and properly see a broken or a leaking gasket. Before you start working on the broken gasket, ensure that the cooling system is drained completely.

Next step is to ensure that the intake and exhaust manifolds employed in the system are completely removed. Follow this by taking out the timing cover, timing belt and timing chain one after another. The valve cover that wraps the engine valve should be taken out next. It is only when you remove the head of the cylinder completely, you will be able to see the head gasket. Give your car a complete once over in order to trace other car engine troubles.

If you intend to put your mind to perform a head gasket repair and replacement entirely by yourself, you have will have to carry out the steps mentioned above in reverse order after the gasket is fitted. Needless to say, this is going to take up a considerable amount of time and missing out on fixing any of the components can turn out to be an absolute disaster. Additionally, you will have to use studs for the engine to ensure torque functionality.  There’s a pretty good chances that the studs may have expanded already due to earlier torque and thus should be discarded completely.

While the job has heavyset technicalities attached to it, it is recommended that head gasket repair and replacement shouldn’t be taken up as a DIY project. This job needs a proficient technician like In Town Automotive considering the series of tests required before and after replacing the gasket. Overheating of the engine and white smoke emanating from the exhaust are basic blown head gasket symptoms. One cannot simply determine if the gasket needs to be replaced by just glancing at these symptoms because other issues with the car can also be responsible.

But, if you are going to execute the replacing of the head gasket on your own, you might as well do it properly employing each step with absolute care.

Given below is the A-Z guide that will be your gospel to analyse and replace faulty head gasket of your vehicle.

Part 1 – Collect Information and Supplies

Before you embark on the project, here is a list of materials you will require:

  • Cylinder head gasket kit
  • Engine oil
  • Engine oil filter
  • Spark plugs
  • Safety glasses
  • Torque wrenches (⅜” and ½” )
  • Code reader (optional)
  • Cylinder for old engine oil and coolant
  • Drip pans
  • Engine thermostat
  • Gloves
  • Tool set for mechanics with multiple socket and wrench combinations
  • Valve cover gaskets
  • Vehicle service manual
  • Timing belt set which is specific to your vehicle
  • Intake manifold gasket kit
  • Exhaust manifold gasket set

Step 1 of Part 1 – Locate the VIN

vin number

Gather information related to vehicle which is both specific and applicable to your vehicle. This is to make your hunt for the car components more simplified.

Your vehicle comes with two very important stickers. You will get information regarding the size of your engine with the help of the emissions sticker under the hood. The label inside the door jamb of the driver’s seat will show the vehicle identification number or VIN.

Step 2 of Part 1 – Find a vehicle service manual for your car

Knowing the size of the engine is integral as a number of engine designs vary and the components differ from one another.

Tip: The service manual of a vehicle is usually much more detailed than the vehicle owner’s manual. The service manual will contain of essential information and will also comprise of simple repair and car servicing procedures.

You will be able to locate this easily at several auto parts store and online vendors. If you do not find a service manual for your vehicle on the shelf, request an associate about placing an order for one. They are fairly cheap and the information it holds is very useful.

The service manual mentions the special tools that will be required for repairs and will state which car parts to leave out while the repair process is on. It may be mandatory to supervise the procedure a couple of times before you start with it yourself.  It is best to get acquainted with the work you are going to perform before you begin dismantling your car’s engine.

Tip: When trying to locate a cylinder head gasket, try purchasing a complete one that consists of many different seals. Even if these kits have seals that you might not really need or has duplicates, it is always better to have a seal when you really need one instead of not having any at all.


When any car component is taken out, any related seals will have to be switched so as to eliminate the likelihood of potential leaks at the time of engine reassembling. Once the seals are replaced, it is important that you apply fasteners for each component at the required torque arrangements.

Contact us today to find out more about replacing head gasket. While you are at it, check out other services that we offer.