Engine valves are supposed to open and close rapidly to allow air and fuel to charge inside the combustion chamber. After the fuel ignites, waste gases flow out through the exhaust valve. If the valve does not open and close at the right times, gases cannot flow back and forth correctly. If there is a problem with an engine valve, you may hear a noise or see smoke.


Noises Coming from the Engine


A ticking noise coming from the engine is known as a valve tap. If the noise is coming from the upper end of the engine, it could be caused by insufficient lubrication. This could be due to low oil pressure. The oil passages could also be blocked because of engine sludge or poor maintenance.


If you hear a valve tap, you should take your car to a mechanic. The lack of lubrication could cause the stem and valve guide to wear quickly, which could cause the engine to fail. Addressing the valve tap quickly can solve a problem with low oil pressure.

You might be able to solve the problem by replacing the oil pump. If the oil passages are blocked, that can also be corrected. You can clear the oil pick-up screen by flushing the engine or removing the pan and cleaning it. You can also clear the oil lubrication galleries with mechanic’s wire and solvents.


Smoke Coming from the Engine


If the engine is smoking, it could be caused by a problem with the engine valves or worn piston rings. If you see a puff of blue smoke when you start the engine, the problem is probably due to excessive valve guide clearance or worn valve seals.


If your engine smokes continuously or when you accelerate, it is probably caused by a worn piston or oil control rings. This can be confirmed by performing a wet and dry compression test.


The engine valve seals should also be checked for dry rot and wear. The guide clearance should be measured with a dial indicator and compared to the manufacturer’s specifications. If there is too much clearance, oil can get drawn down from the intake and exhaust valve guides. It can then be burned in the combustion chamber with the air/fuel charge. This can cause bluish smoke to come out of the tailpipe.


If the smoke is caused by a problem with the valve train, it can often be solved without replacing the engine. Worn valve seals can be replaced without needing to remove the cylinder heads.


If the smoke is caused by excessive valve guide to stem clearance, knurling the valve guides can be a temporary solution. This is a process that uses a special tool to restore the proper clearance by cutting into the guide and raising the metal on either side to decrease the inside diameter of the hole where the valve fits. A finishing tool flattens the new ridges to allow the engine valves to move smoothly in their bores.


Burnt Engine Valves


If an engine valve is damaged and no longer seals off the combustion chamber, it is considered burned because it causes heat damage to the engine. A burnt valve makes a popping sound on the combustion stroke of the cylinder. If the popping sound comes out of the tailpipe, the problem is with the exhaust valve. If the sound can be heard through the throttle body in the engine compartment, it is caused by an intake valve. The cylinder involved can be isolated with a compression test.


Where to Find Auto Parts to Repair Your Vehicle


If you hear a noise or see smoke coming from your engine, it could be caused by a problem with an engine valve. You should have it repaired as soon as possible to avoid costly damage to your engine.


AOK Valve Stem Seals Ltd. has made concrete contribution to valve seal industries for over 10 years. The company supplies high quality valve seals for cars such as Alfa Romeo valve seals, BMW vehicle valve seal, etc.


If you are looking for various rubber parts, oil seal, or others, please do not hesitate to contact with AOK through phone call or by email.



Article Source: https://www.bishopsautoparts.com/content/how-tell-if-your-vehicle-has-engine-valve-problem