In a combustion chamber where precision is critical, something as small as the size of a pin can make all the difference. Piston rings are a small but important part of the compression process that most don’t understand.
They are simple at first glance, but in fact, they perform one of the most obvious and most important tasks in combustion. Therefore you need to know bad piston ring causes and fixes.
Each ring plays a different role. Together they help seal the combustion chamber, lubricate the cylinder walls, and allow heat transfer. When piston rings are worn or damaged, many different problems can arise that not only make driving awkward but also pose a potential hazard to the engine.
However, as internal components, they are not easily accessible. So if they are worn, it would be impossible to manually assess their condition.
However, you can pay attention to some of the symptoms of poor piston ring conditions to take appropriate action and avoid significant engine damage.
Before we go into bad piston rings causes and fixes, we should first understand what the piston rings really do.
Piston rings are basically just metal rings along the side of the pistons. They undertake a few very specific tasks which are important for your vehicle’s peak performance. There are three piston rings which each have tasks.
These rings each have gaps between them which help them expand and contract according to the temperature of the pistons.
There are three rings, first the upper ring seals off the combustion chamber making sure that none of the combustion gases escape, which could be really bad for your engine. This ring is referred to as the compression ring in respect to its function.
Then we have the lower ring. This ring contains holes that are used to scrape the oil off the cylinder walls and is known as the scraping ring. The third ring however does not have a specific job of its own.
Here are the functions that piston rings serve.
This is the most important function that is carried out by the piston rings. As the piston compresses gases try to escape. The compression ring seals off the gasses so they can be easily compressed and more importantly make sure that the gasses don’t work their way up to the crankshaft.
However, it’s impossible to stop all gasses from leaking out because even though the compression ring does its job, small amounts of gasses leak through.
But the compression ring keeps it to a small amount so it doesn’t impact your engine performance much. So, it allows you to maintain a stable compression ratio which is very important to the performance of your vehicle.
The piston rings bridge the gap between the piston and the cylinder wall. The piston rings are the only contact points that help heat transfer from the piston to the cylinder walls. This removes a lot of heat from the fuel conversion process while also taking huge amounts of thermal stress from other rotating components.
Moving down to the last and the third ring. This ring helps lubrication by scraping the oil off the walls of the cylinder. The piston ring does this by scraping the oil off the walls and sending it through holes that are in the piston ring through to the crankcase.
This makes sure that there is a seamless and trouble-free movement of the pistons in the cylinder and prevents any abrasive contact.
Eventually, as time goes by, the piston rings wear. And you should probably change it then, but there are some reasons that this could be happening faster than supposed to.
They could be your own practices or factors associated with the piston rings themselves. There are factors that can produce excessive piston wear, so you should try your best to avoid them.
As the pistons move up and down in the cylinder, the piston rings have the job of ensuring that they allow adequate heat transfer and move smoothly.
If the lubrication is insufficient or the oil is contaminated with grinding particles, it will cause the piston rings to wear prematurely. Further, it will also contribute to the damage along the piston walls.
You can prevent this problem by checking the engine oil regularly and changing it at the recommended intervals.
In the combustion chamber, timing is everything. Without properly synced ignition, things can go wrong. Improper combustion is known to cause internal damage. The most noticeable of which is your piston rings.
In older engines, the crankshaft and camshaft synchronization may be turned off. Which can also lead to an incorrect synchronization. And even if the timing isn’t entirely up to you, you can still look for such anomalies at the car service you’re planning on doing.
The most common cause of premature or rapid wear of piston rings is overheating of the combustion medium. It is never advisable to let the engine overheat uncontrollably.
Causes of overheating can vary, although in most cases it can be corrected with simple maintenance practices such as checking the coolant level, water level, radiator, and cooling fan condition.
Manually assessing the condition of the piston rings is virtually impossible to do by yourself. This is because you would have to take apart the whole engine just to check on the pistons.
There is no way you could assemble the engine back to its original setting. And even if you do decide to hire a professional to do it for you, this is not the most practical approach.
The good news there are other symptoms that you can use to identify whether your piston rings are working properly. Here are some symptoms of bad piston rings.
Piston rings regulate compression and lubrication. Therefore, when your piston rings wear out and you lose compression and you are not lubricated enough.
This causes the car to lose its accelerating power. The car will have a hard time accelerating when you step on the gas pedal and the engine will take longer to respond and speed up your maneuvers.
Decreased acceleration can also be caused by a damaged valve seal. So run a compression test to see if you have a bad piston ring or valve seal. Higher compression is a symptom of a poor valve seal, whereas lower compression means the piston rings are damaged.
As noted above, the loss of compression slows acceleration due to inefficient engine speed, causing the engine to stall. In extreme cases, a bad piston ring can cause you to lose all engine power and may have to tow your car. Minor problems with the piston ring can only result in poor motor performance.
Complete engine shutdown will only occur if you ignore the initial symptoms of a damaged piston ring and continue to use the car without taking it to a mechanic for inspection
When the check engine light comes on due to excessive oil consumption, you most likely need to replace your piston rings.
Worn piston rings cause oil leakage in the combustion chamber, which automatically results in higher oil consumption. Therefore, check the engine oil level regularly.
As a result, your car will need to be refilled with oil more often than the average 4,000 miles. Check your piston rings right away if your car starts to use more oil than usual. This can be a very obvious sign that you have bad piston rings.
When the piston rings are bad, there is high pressure in the crankcase. This will damage the engine seal and cause oil to leak. If you notice many different oil leaks, be sure to check the crankcase pressure.
You can do this by turning off the engine and slowly opening the oil cap. There should be no pressure but a small vacuum. If the oil cap comes out with a lot of smoke, you may have a bad piston ring.
When the piston rings are worn, engine oil finds its way inside the pistons. This causes the engine oil to burn along with the fuel. This will cause a lot of smoke to be emitted via the exhaust pipes. A cloud of white smoke will be emitted with a tint of blue or gray when engine oil is burnt.
If you smell burning oil when the smoke comes out, it probably means your engine oil has entered the internal combustion chamber. The blue and gray smoke from the exhaust will show that for sure.
An increase in oil intake is often caused by blow-by when the air-oil mixture in the combustion chamber flows through the piston rings installed to create more pressure in the crankcase.
When positive ventilation flows from the positive crankcase ventilation hose (PCV) back to the crankcase, a large amount of exhaust gas is discharged and the intake air is very oily. Oily intake also causes an increase in oil consumption.
A blow-by is the leakage of the fuel and air mixture to the crankcase. Most blow-by occurs when exhaust gases enter the crankcase and pass through the piston rings.
The two main causes of wear on piston rings and most engine parts are contamination. Dirt enters the engine through a faulty air filter. Dirt can also reach the engine through the oil chain from contaminated oil. So, here’s the simplest way to extend the life of your piston rings.
Regular oil changes ensure the oil in your engine is clean and residue-free. This prevents useful metal parts such as piston rings from rusting. Although the oil filter removes dirt, sometimes the oil circuit is not cleaned properly.
Dirt particles that are already on the clean side of the oil circuit enter critical parts of the engine and cause wear.
When a car’s air filter doesn’t work effectively, it causes an oil leak. This allows easy access to dirt and other pollutants. If you replace the air filter in time before it breaks, you increase the chances that your piston rings will last longer.
The piston rings are inside the internal combustion engine. If the piston ring in your car ever breaks, you need to think carefully about whether to replace it or not. Replacing the piston rings requires disassembling the engine, which is very time-consuming and expensive.
This is also a very risky procedure as it is difficult to reassemble the machine in its original setting. Therefore, you should only replace the piston rings if there are no other options.
If the piston rings are damaged and not worn, you must replace them immediately. However, if your piston rings are starting to wear out, you may have some free time before you need to replace them. The first visible symptom of a bad piston ring is white and gray smoke coming from the exhaust.
This is a sign of engine oil leaking through the piston rings and into the combustion chamber of one or more engine cylinders. Smoke is produced by the burning oil in the chamber during the combustion process.
When white and gray smoke comes out of the exhaust, you’re also using more engine oil. But because there is an oil leak, there is less oil in the engine. This will cause the engine to overheat and potentially damage engine components.
All of these are big issues that need to be resolved quickly otherwise your machine may suffer irreparable damage.
Your vehicle can last several weeks just by changing the oil constantly to fix leaks. However, your engine will not be able to produce as much power as before.
So there is no point in waiting even a few weeks to replace your piston rings. As soon as you see white and gray smoke coming out of the exhaust fumes, take your car to a mechanic and have the source of the problem investigated. If you find your piston ring is damaged, replace it immediately.
Many of the symptoms associated with worn piston rings can also be caused by a poor valve seal. Therefore, it is important to differentiate between the two and know where the problem lies with the machine.
A common method used by mechanics to determine failed internal components is to perform a compression test. Normal compression tests tell a lot about engines health, though PSI levels alone don’t tell the whole story.
Here you need to refer to the specific area commanded by each component of the running vehicle. If the exhaust emits loud sounds during the compression test, it means the exhaust valve is faulty. When the fuel injector makes noise, it means the intake valve has a problem.
For piston rings, do a test by adding a little lubricant. If the pressure gauge jumps, it means the piston rings are dirty.
However, such problems are quite difficult to diagnose for a definite answer and almost always require machine tape. It is best to take precautions to avoid internal damage to the machine.
Once you confirm that you have faulty piston rings, you need to think about getting them replaced.
Piston rings are small but expensive to replace. This largely depends on the make and model of your car, but on average you can expect to pay anywhere from $40 to $200 just for a piston ring. It doesn’t sound like much, but wait until you add labor costs to the total.
Since the piston rings are deep inside the engine, the mechanic must disassemble the engine and remove the old piston rings and replace them with new ones. This whole process takes time and requires precision.
After the new piston rings are installed, the engine must be installed and reassembled. Your mechanic will need 16 hours or more to complete the job. Certified mechanics will likely be faster and more likely to do it the right way.
To properly install the piston rings, you must measure the ring caps and place them in the correct order. In addition, before installing a new piston ring, you should also check and measure the wear on the cylinder walls.
For a proper piston ring replacement, you can expect to pay anywhere from $1000 to a whopping $4000 for labor depending on the engine.
Ultimately, you could up paying up to $5000 for a piston ring replacement.
Though you can save a huge chunk of the replacement cost, if you do the repair yourself, it is never advisable. Disassembling an engine is a complicated process and needs to be done right. And chances are, you do not have all the necessary equipment to take on such a huge process.
In addition, you could end up with more parts to replace because after you disassemble the engine, there is a chance that you could spot whole load problems while inspecting the other components, which you won’t be able to examine unless you disassemble everything.
So just in case, getting it done by a professional certified mechanic is recommended.
Here are some of the most common questions regarding bad piston rings causes and fixes.
Piston rings are usually built to last as long as the engine, lasting somewhere from 50,000 miles to 250,000 miles. But the usual life expectancy of piston rings comes at about 100,000 miles. So if you conduct proper maintenance you should have no problems with the piston rings.
Yes, you have to add enough oil to lubricate the piston rings during installation. You should always use oil while installing because if you don’t there could be abrasions in the cylinder wall which could release contaminants into the oil.
So you should always remember to add enough oil to lubricate the piston ring while installing. But just because you have to add oil doesn’t mean you have to dip the piston ring in a quart of oil.
A broken piston ring causes rattling and knocking sounds while your engine is running. The rattling of a broken piston ring is pretty hard to ignore. The rattling sound will soon be followed up by engine misfiring and engine knocking.
Depending on the make and the model and the problem at your hands, it is unlikely that replacing will cost less than rebuilding. Since most engine parts are very costly and require you to buy other connected components if they malfunction.
When you have bad piston rings or other problems like head gasket leaks, valves, or cylinder wall leaks misfires can occur. If you notice white smoke coming from the engine that could mean that the piston rings aren’t able to contain the compression gasses properly.
Piston rings will expand as the engine warms up, you should account for this while you install the piston ring. If the gap is too big the engine will have crankcase pressure, have a lot of blow-by and lose a lot of oil.
If the piston rings are reversed from their position, it will cause the piston rings to scrape the oil up and into the combustion chamber. Which means you’ll be burning precious engine oil every second that you are driving your vehicle.
If you don’t leave enough space for the piston rings, as the piston rings heat up they will expand which will cause the rings to run into themselves. And this expansion causes great amounts of stress on the cylinder walls, and ultimately the piston ring will crack from the pressure.
Piston rings are one of the tiniest components in your engine. At first sight, you might think it is an insignificant part. On the contrary, it is one of the most important pieces that keep your engine functional.
There can be many reasons why your piston rings are wearing off. While not every one of them is under your control, with proper maintenance, you could drastically increase the life span of piston rings.
Fixing piston rings is not an easy job. It takes a lot of time, skill, and experience. That is why we recommend that you get it done by a professional if necessary.
Once you get a scope on piston ring replacement cost, you probably understand the importance of properly maintaining it so it does not wear out prematurely.
