What are some car engine oil leak sealers?

This blog post will answer the question, ‘What are some car engine oil leak sealers?’, and cover topics like causes of an oil leak in a car engine, and inspection and diagnosis behind an oil leak in a car engine.

What are some car engine oil leak sealers?

These are some characteristic engine oil sealers that help to stop oil leaks from a car engine:

  • The Lucas Oil 10278 Engine Oil Stop Leak is a popular oil leak sealer and is free of any hazardous solvents. It also offers a boost to the car’s performance by increasing the oil pressure, however, it only works on petrol engines.
  • The ATP AT-205 Re-seal Stop Leaks helps in fixing multiple components associated with the fuel system and can work on any engine type. The downside lies in the fact that this causes oil thinning and sometimes generates blue smoke.
  • The Liqui Moly Oil Leak Stop helps in the reduction of engine sound and improves fuel economy, however, they are not advisable for application on cars with automatic transmissions.

Causes of an oil leak in a car engine

There are many potential causes of oil leakage in a car engine. They are as follows:

  • A leaking engine oil gasket can cause the crucial engine fluids to spill out onto another component.
  • Leaking oil pans
  • Loose oil seals
  • Poor connections
  • Leaking timing and valve cover seals

Inspection and diagnosis of an oil leak in a car engine

Inspection should be first carried out on the oil plug seals and other seals belonging to the timing cover and valves. A defective oil pressure sensor might also be a contributing factor behind an engine oil leak.

Fixing the oil leak by using an additive

Oil leak additives are very useful for sealing all the components inside an engine to stop them from leaking. It should be noted that the leaks might take a lot of driving to get completely sealed.

Using certain automotive tools to fix an oil leak

Using a torque wrench and a socket of 10mm size to check for loosened bolts on the oil pan is another method that can be followed. The car must first be elevated using a jack to access the oil pan easily.

The bolts often get worn out, thus getting loose and leaking as a result. Hence, it is necessary to tighten these bolts as soon as possible.

Fix involving valve cover gaskets and spark plug seals

Valve cover gaskets and spark plug seals are essential for preventing the leakage of oil. These gaskets and seals get worn out or cracked over time and cause oil leakage. 

However, in order to access the valve cover gaskets and the spark plug seals, the valve cover itself needs to be removed as it acts as a housing for the gaskets and seals underneath.

To remove the valve cover first, we need to unplug the hoses connected to the top of the valve cover. A big screwdriver can help pry off the hoses with a small application of pressure.

After the hoses are removed, we need to remove the valve cover. A 10mm socket and a ratchet will help in loosening the bolts that hold the valve cover to the engine. 

After removing the bolts, if the valve cover sticks to the engine, use the big screwdriver and apply pressure to pry it off. It is observed that the gaskets are cracked and the spark plug tube seals come off easily as they have become brittle.

Use a buffing tool to remove any excess sealing material so that the spark plug cavities look shiny as new. Use an oil pump to suck the residual oil out of the cavity after taking out the spark plugs. 

The spark plugs can be cleaned by an electrical power cleaner to get rid of the excess oil. The gaskets and spark plug tube seals often come in one piece and can be fitted after all the above steps have been taken.

Reconnect the valve covers and the hoses and test the engine by turning it on for any further oil leaks.

Fix in case of leaking or burning of oil

Engine oil leakage can be spotted by either noticing blue fumes from the tailpipe or engine puddles underneath the car. In case of engine oil leakage, a UV leak dye can be used as a fix.

To perform this fix, pour some of the UV leak dye into the engine oil and with a UV light and a pair of yellow UV sunglasses, look for the green-colored markings on the engine to locate where the oil leak is occurring.

If the leaks are absent but the car is still losing oil, the problem is most likely the burning of oil. This mainly happens due to a clogged PCV(positive crankcase ventilation) valve that sucks oil into the engine and burns it.

A PCV valve sucks the exhaust vapors that were released after combustion and sends them to the cylinders instead of the exhaust along with the oil from the crankcase. A clogged PCV valve is caused due to it being stuck open and sucking in oil from the engine instead of the vapors and burning it in the engine.

Follow the PCV hose and locate the PCV valve. Take it out and consider replacing it as it costs only a few dollars.

Fix involving burnt spark plugs

If none of the other issues are present and the car still loses oil, the problem might be a burnt spark plug. This is indicated by the charred appearance of the spark plug base. This means that the engine has a serious internal problem that is caused due to bad valve seals or worn-out piston rings.

Consider replacing the spark plugs as they are cheap and easily available at any automotive repair shop.

Research shows the best additives that can stop an oil leakage inside the engine.


This blog post addressed the question, ‘What are some car engine oil leak sealers?’

We understood the various causes that contribute to an engine oil leak and also came across certain inspection and diagnostic methods to tackle an engine oil leakage problem. Please feel free to comment on the content or ask any questions in the comments section below.

Frequently Asked Questions (FAQs): What are some car engine oil leak sealers?

How much Oil Stop Leak should I use?

This is a useful additive to curb oil leaks and only about 20% of the total storage capacity should be used.

What are the most likely places for an oil leak?

The most likely places for an oil leak include the valve cover gaskets, spark plug tube seals, oil pans, and oil filters.

How long does Lucas Oil Stop leak take?

The Lucas Oil Stop leak takes about 500 miles to completely seal the oil leak. It is important to keep the engine oil levels in check until the process is completed.