Six signs that your valve seal is leaking
The valve seal,also known as the valve stem seal or valve stem oil sea, is a crucial component of an engine's valve system. Designed to prevent oil from leaking into the combustion chamber, valve seals provide better fuel efficiency, reduce emissions, and protect the valve train.
Product Description: Valve seal
The valve seal,also known as the valve stem seal or valve stem oil sea, is a crucial component of an engine's valve system. Designed to prevent oil from leaking into the combustion chamber, valve seals provide better fuel efficiency, reduce emissions, and protect the valve train.
Function:
Valve seals play a vital role in maintaining the optimal performance and longevity of an engine by serving several key functions:
1. Oil Sealing: A primary function of valve seals is to prevent oil from entering the combustion chamber above the valve. By sealing the gap between the valve stem and the valve guide,they prevent oil from leaking into the combustion process. This ensures the correct air-fuel mixture. improving fuel efficiency and reducing the release of harmful emissions.
2. Lubrication: Valve seals help in lubricating the valve stem.,reduce friction between moving parts, and preventing premature wear. Proper lubrication ensures smooth opening and closing of the valves, promoting efficient engine operation.
3. Heat Dissipation: The valve seal also assists in efficiently dissipating heat from the valve stem,preventing overheating and reducing the risk of valve damage.
Six signs that your valve seal is leaking
1. Conducting a Cold Engine Test
One of the best ways to tell if you have a faulty valve seal is to conduct a cold engine test. After your machine hasn’t run for a while — even overnight — the seal is now cool. Once you start the engine, the seal will contract. Damaged seals will leave a small gap. Leftover oil will then settle at the top of the valve cover head.
When you start the engine, you may also see blue-tinted smoke appear from the exhaust. If this happens, it means the residual oil is passing down through the damaged seal and into the combustion chamber. The bluish smoke, which is burned oil, signifies that the engine needs a new seal, even if it clears after several minutes of running the engine.
2. Increased Smoke Levels
Depending on the machines and equipment you use, smoke is often a common form of exhaust. However, when you start seeing it last longer than usual or appear a different color, you know a faulty seal may be the cause. The excessive smoke may also come in more consistent waves as the engine runs for long periods. Be aware of specific machine movements that cause more smoke than usual.
3. More Oil Consumption
If you notice you’re going through more oil than usual, it can be another indication of a bad seal. When oil leaks or burns at higher rates, the seal no longer controls the oil flow. Burning oil increases emissions and can contaminate the catalyst. Unburned fuel in the exhaust skyrockets the converter’s operating temperatures, which can cause the converter to overheat and create a blocked exhaust.
Make sure to check the engine’s oil level with a dipstick, and refer to your oil log to see if the fluid levels differ. You can make this part of your regular maintenance schedule. While oil leaks are often a clear warning of faulty valve seals, they may not always be visible, so don’t rely on this as a guaranteed warning because the oil could be burning off.
4. Engine Idling
Pay attention to your machines if they ever idle. When the engine is at rest, high vacuum levels can cause the oil to build around the heads of the valve system while the valve is closed. If the seal is faulty, you may once again see blue-tinted smoke when the engine begins to run. That means the oil is getting pulled past the seal and into the valve guide. Make sure to shut the engine down and remove it from operation until you can get it repaired.
5. Compromised Acceleration Power
Depending on the engines you use in the oilfield and agricultural industries, testing the engine’s compression can also help determine if your valve stem seals are deteriorating. If the machine has a higher compression level, you have a valve seal issue and you'll need replacements. On the other hand, a lower level may designate a piston ring malfunction.
6. Engine Misfiring
An engine with broken seals can cause oil to build on the electrodes of the engine’s spark plugs. As a result, plug fouling can occur, which is an accumulation of carbon deposits that can cause engine misfires. As carbon buildup increases, so does compression, leading to engine damage from faulty detonation or even issues with pre-ignition.
Knowing these six signs of valve stem seal failure can help you mitigate the issue before problems like oil leaks and high compression levels begin. The sooner you notice different-colored smoke, an increase in oil usage, misfiring engine startups and idle noises, the faster you can make the necessary seal repairs. In return, your operations will remain efficient, productive and safe.
How to check the valve stem seals
Step 1
Open the hood to the engine and check the oil level of your machine using a dipstick. Is it significantly lower compared to other times after a similar amount of usage? You can also check to see if there is any excess clearance between the valve stem and guide. Leaks are an obvious sign the valve stem seal has issues — but these aren't always present, even when the seal is failing.
Step 2
Start the engine and observe the exhaust. Is there a lot of smoke coming out of the pipe, and does it have a blue-gray tint? If so, the engine is burning leaked oil — which is why you may not see any leaks under the hood.
Step 3
Listen for odd noises like rattling or tapping as the engine idles. Any unusual sounds can indicate problematic valves.
Step 4
Check for engine and error lights that can indicate a problem. You can hook the machine up to a diagnostic reader to scan for different error codes. For example, valve seal and valve guide issues will read as specific codes, so reference the owner’s manual for assistance.
Step 5
If worse comes to worst, you will need to disassemble the engine and inspect the valve stem seals and other components. Relying on the professionals for this step may be best to ensure more parts do not get damaged throughout the process. You or the expert should look for dented, cracked, broken or deteriorated valve seals.
Valve stem seals' replacement costs are affordable in the long run because new seals prevent more catastrophic engine damage.
Fast valve stem seal replacements are just as essential as choosing a manufacturer that knows the vitality of a well-designed valve stem seal. Look for custom solutions that can fit your specific requirements if your machines are unique to your industry or operations.
You will want to invest in top-tier solutions that are free of defaults. For example, CDI has an inventory of rubber seals that provide an elastomeric seal for your engines. We focus our valve seal portfolio on durable, temperature- and chemical-resistant solutions. We can also manufacture any customized rubber compound to fit your unique needs.