What Causes Crankshaft Seal To Leak?

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The vehicle crankshaft is an important component of the engine. With the component, the oil coming into the engine gets bounced back into the oil pan.

This purpose is to ensure that the engine receives enough oil needed to power the car. This way, too, the engine can maintain the proper oil level.

The crankshaft receives enough lubrication when working under high pressure. It needs enough oil to keep the engine working.

The crankshaft has two seals that prevent oil from leaking onto the ground.

One of the crank seals is located behind the engine, at the back of the flywheel; the other sits at the anterior of the engine, a little at the fore of the crankshaft harmonic balancer.

These seals can leak. When they start to leak, the seals can cause a lot of issues to your car, beginning with the engine.

So, what should you do in this instance? Read and find out in this guide.

In this article, I will take you through the types of crankshaft seals, how to determine if your oil seal is leaking, the causes of oil seal leak, how to fix a leaking oil seal, time to replace a crankshaft seal with a new one, and how to fix the two types of crankshaft oil seals.

What Causes Crankshaft Seal Leak?

There are several reasons your car crankshaft seal can begin to leak. The most basic and visible reason your crankshaft seal can leak is the troubling wear and tear experience.

The maximum mileage for your crankshaft seal is s 100,000 miles and once your car has reached that milestone, you can be sure the crankshaft can start to raise issues.

There are other issues that can trigger crankshaft leaks. They include:

  • Collision
  • Faulty gasket
  • Wrong installation
  • Excess engine oil
  • Seal damage during installation

I will later explain how each of the reasons causes your crankshaft seal to leak.

But let’s look at what a crankshaft is and the types of crankshaft in your car. This will be a great starting point, trust me.

Crankshaft And Crankshaft Seal Location

The crankshaft seal is located near the frontal part of your car engine that secures the edge of the crankshaft.

The corks are disc-like shaped and mainly composed of metals or plastic; they’re one of the smallest, affordable yet crucial parts of an engine.

Also, they’re generally attached to the forepart of the turning cover and likewise seal the edge of the crankshaft while it rotates.

The component comes with a metal and rubber seal that links the crankshaft to the timing cover.

Without the seal, -which can also be made of silicone, these two other ends will tell apart. As a result, the engine will not function optimally.

Types Of Crankshaft Seal

There are two kinds of crankshaft seals which are the rear main bearing crankshaft and the front main bearing crankshaft:

The Rear Main Bearing Crankshaft Seal: The rim outside the rear main bearing cork generates a seal between the engine block and the oil pan.

The Front Main Bearing Crankshaft Seal: This seal prevents lubricants from leaking from the engine. It is found on the crankshaft pulley on the side of its generator and timing belt.

These crankshaft seals on the two engine closures help to prevent engine oil from leaking out of the lubricated crankshaft.

How To Know If Your Crankshaft Seal Is Leaking

You need to recognize the signs of leaking in your carburetor seal to know when to mend or replace it. Below are some of the symptoms you’d notice for you to be convinced that your seal is leaking.

Unusual From Your Engine

Having bizarre sounds emanating from your car could be a sign of its carburetor seal leaking. However, this sign might be spurred by something else wrong with your car.

Therefore, you must keep reading to find out the other sign of cork leaking that you must watch out for in your car’s engine.

Engine Oil Droplets Around The Automobile

One major sign to identify crankshaft seal spilling is by seeing a small/large puddle of oil around your car.

This is often a regular occurrence which is the main pointer that your crankshaft spill is leaking.

After observing this, the next thing is to decide whether to repair the seal or to completely change it.

Leaking Crankshaft Seals: Explaining The Causes

So, let me explain the various causes of leaking crankshaft seals. Your crankshaft seal might be leaking due to the following reasons:

Wear And Tear

This is the most common reason for crankshaft cork leaking. This happens after a crankshaft seal has been used for a long period (about 3 years of usage or if the automobile has 100,000km-150,000km).

Meanwhile, when this occurs you need to immediately replace it with a new one to prevent harm to your vehicle’s engine.

Collision Of Seals On Hard Surfaces

Your crankshaft cork will ooze out lubricant if you constantly hit your car with hard surfaces when driving.

Additionally, apart from driving roughly leading to serious damage to the interior part of your car, it also wrecks the look of your car.

Improper Installation Of Crankshaft Seals

After the case of wear and tear that leads to replacing the crankshaft seal, the seal may persist if the new seal is not properly installed.

Thus, it is important to allow a competent mechanic to accurately install your crankshaft seals once a replacement is required.

Having Excess Lubricant In The Engine

A seal will undoubtedly leak if they’re filled excessively to the brim. As a result, there is an overflow of oil in the interior part of the engine.

Also, if there’s no space for the oil to occupy due to excess of it, it will overflow. The inside of the engine should not house too much oil or oil deposit.

When it is in excess, oil can form grime, gunk, and carbon deposits that can clog the passage of the oil.

Time To Replace A Crankshaft Seal With A New One

By now, you should be asking what time is best to replace a crankshaft seal. A carburetor cork should be changed when the following occurs.

  • After the seal has been used for a maximum of 3 years: It doesn’t matter even if it doesn’t have signs of wear and tear on it. After reaching its mileage, you should consider changing the seal and replace with a new one.
  • When constant enormous oil leakage occurs: the other reason you should consider changing the crankshaft seal is if there is too much oil leakage. Excess oil around the engine is not good for the safety and lifespan of your car. As much as possible avoid oil leak or when it occurs, try to fix them.
  • Frequent overheating of the car’s engine: This is a dangerous sign, I must say. Don’t even think for a second before you replace the crankshaft seal. Once the engine keeps overheating or high internal combustion occurs, it’s time to get rid of the seal.

How To Replace A Crankshaft Seal

Although crankshaft seals are very much inexpensive, they’re vital and highly required by an engine.

Also, once a seal is cracked, the best thing to do is to replace it immediately. This is to prevent it from causing any harm to the engine of your automobiles.

Meanwhile, the rear main crankshaft oil is more basic and simple to replace. But, the front main crankshaft oil seal requires more steps in replacing, and you’ll need a bit of external support to get it done.

The steps below are to be taken when you want to replace your crankshaft seals:

Rear Main Crankshaft Oil Seal

  • Remove the seal using a screwdriver and then clean with spray cleaner to remove any grease or dirt on it.
  • Apply lubricant to the surface and the workpiece before screwing it back tightly to the crankshaft.
  • Ensure that the new carburetor seal is well fitted to its position.
  • Afterward, bring the engine oil to normal, check if the seal is well secured before starting the engine.

The Front Main Crankshaft Oil Seal

Get the required simple tools and a grease remover with a clean rag.

  • Apply brakes to the car.
  • Remove the pulley nut, service belt, and the right wall.
  • Discard the belt drive and the carburetor’s gear.
  • Then, gently clean the seal and its surrounding with a clean spray and a rag.
  • Lubricate the workpiece and its shaft before securely fitting it back to its previous position.

Final Thoughts

A crankshaft is found near the end of an engine that holds up the end of the crankshaft. It shouldn’t be ignored due to its small size and how cheap it is.

This is because without it functioning properly there will be a shortage of oil in the engine.

Furthermore, oil shortage in engines could result in friction and other problems for your automobiles.

Eventually, I believe you fully understand everything I discussed in this article. If you have any questions relating to crankshaft oil seals, then do leave them in the comment section.