Why is my Motorcycle Leaking Oil An Engineer’s Explanation

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Motorcycles are easy machines. However, there are some things that motorcycle owners need to be aware of. Engine oil leaks could be one of these things.

Motorbike engine oil leaks can seem a little scary and mysterious. This is because there could be many causes. Motorbikes are prone to oil leaks.

My motorcycle is leaking oil. Two main reasons a motorcycle may leak oil are: Faulty gaskets on the oil pan and valve cover, crankcase or cylinder heads of an engine are the first. A second common source of oil leakage is caused by faulty plugs like the oil drain plug and crankcase side inserts.

I have owned more than a dozen motorcycles, and had oil leaks on most of them. My experience as an engineer and my knowledge of the mechanics allow me to clearly explain the causes and how to prevent them from happening again.

Why a Motorcycle Leaks Oil

Oil leaks can cause a lot of problems and can even be quite messy. It’s embarrassing parking a leaking motorcycle in a public place only to find that there’s a nice little puddle underneath it.

You’re not alone if you’re frustrated with your motorcycle leak. This happens to all motorcycle owners, even those who take great care of their bikes.

Motorcycles that leak oil are most often caused by faulty gaskets. The main gaskets that leak are the oil pan, valve cover gasket and crankcase gasket. These are the four most common gaskets to leak in a motorcycle engine because they see the highest internal pressure and oil can push out between those meeting surfaces if they aren’t doing their job.

I’ll use the picture above as a better visual reference. The oil pan gasket can be found at the bottom, just behind the exhaust. The valve cover gasket can be found on the top of your engine (red circle). The crankcase gasket can be found on the side of your engine (yellow circular). The cylinder head gasket can also located in the middle of the engine, usually near the bottom of your fins (blue circle).

Gaskets will eventually shrink, crack, and lose their effectiveness. The constant pressure on the gaskets causes oil to leak from the weak points, causing leakage.

People don’t realize that leaving a motorcycle dormant for long periods of time can have a negative impact on gaskets. Gaskets expand and heat up when a motorcycle is regularly used. The gaskets are also known as “gaskets”. “exercised” and last a lot longer when they’re used. They become more fragile if they are not used.

A faulty oil plug is the second major reason why motorcycles can leak oil. The oil drain plug at the bottom, side crankcase and valve plug are the most likely to leak.

Oil leaks can be traced to the oil drain plug. Sometimes, motorcyclists may scrape the bottom off their motorcycles on a curb or speed bump. This can cause oil leaks to occur.

There are often plugs at the crankcase’s side to check the timing, stator, clutch, and other items. These plugs are not common on all motorcycles, but they could be the cause of a leak. You will also find plugs on the valve cover that enable owners and mechanics alike to easily adjust the valve lapping. They can also be the cause of oil leaks.

The main reason oil plugs leak is because they aren’t on tight enough. The vibrations of the motorcycle can sometimes cause them to come a bit lose, so make sure they’re all tight. O-rings can also wear out and become ineffective. If those aren’t working right, oil can easily leak. Sometimes, the plugs might not be threaded correctly which reduces the seals that are needed to keep oil in.

How to Fix Oil Leaks

You may have found yourself with an oil leak on your motorcycle and wonder if you’re going to have to pay hundreds of dollars to fix it. Most oil leaks can be repaired by anyone with basic tools.

Easy to install oil drain plugs You’ll need to find the replacement drain plugs either at an auto parts store or online. Check your owner’s manual or research online to make sure you purchase the right plugs. This can be done in your garage in just fifteen minutes.

Most of these gaskets we’ve discussed can also be changed in your garage. To remove valve cover gaskets you will only need to loosen a few bolts. You may also have to remove your gas tank, which is also very simple.

It is also possible to replace the crankcase and oil pan gaskets. Be sure you find instructions online or in your owner’s manual to make sure you do it correctly specific to the type of motorcycle you have.

The cylinder head gasket should be the one you don’t fix. This means that you must remove the top portion of your engine. This will reveal the pistons and other critical parts of the engine that an untrained owner shouldn’t be handling. You could end up damaging your engine if you do not follow these steps.

When replacing gaskets, you will see instructions that recommend using RTV either on one side or both. RTV, a gasket sealer, provides triple protection for your engine and less likelihood of oil leaks in the future.

Many places state that oil can be repaired by using certain additives. While this may be a temporary band-aid, I don’t recommend you do this because this is simply ignoring an underlying problem.

How to Prevent Oil Leakage from Happening

I hope you don’t feel doomed that you will forever have to deal with oil leaks and be constantly fixing them on your motorcycle while you own it. There are many things you can do to avoid oil leaks or make them worse.

You can prevent motorcycle oil leaks by riding your bike regularly. That’s simple enough, right? You probably bought your motorcycle for this reason.

As I mentioned, the gaskets in the engine need to be replaced when they are worn. “exercised” They last longer when they are used. You can think of it as a rubberband. It will eventually snap if it is left in a single place. It will last longer if you keep it in use. Gaskets function in the same manner.

It is important to keep your oil changed regularly. Keeping in old oil with potential corrosive elements inside isn’t good for your engine and it isn’t good for the gaskets either. Although most oil contains additives to keep it from becoming acidic over time, these additives eventually dissipate and oil becomes acidic. Gaskets could be ruined by acidity from oil. Regular oil changes will stop this from happening.

It’s also a good idea to occasionally inspect your motorcycle engine after taking it for a long ride. After your ride, take a moment to look under the motorcycle for oil spots or leaks.

Sometimes, there may be small signs that indicate the start of an oil leak. Some oil may have accumulated in a certain area. However, it will drain off and disappear once the bike cools down. It is much easier to spot oil leaks after a long trip than it is to address them later.

How to Tell Where Oil Leaks Are Coming from

Sometimes oil leaks on a motorcycle can be a little tricky because you don’t know exactly where the leak is coming from. It can be even more confusing because there are many possible locations for oil leaks.

To quickly locate oil leaks, mechanics have a variety of tools. But most of us don’t have tools like that laying around nor do most of us want to spend the money paying a mechanic to find it.

If you don’t know where the leak is coming from, Place a piece or cardboard under your motorcycle first. Assemble the drips with the gaskets.

If that still doesn’t help you track down where the leak is coming from, try using the paper towel method. Wrap the motorcycle in paper towels and secure it with tape after it has cooled. This will take a little bit of time, but the leak will quickly manifest it’s exact location on the engine by soaking through the paper towel.

Similar Questions

My motorcycle is leaking gas. Gas leaks from a motorcycle usually because a hose isn’t on tight, a gasket is worn, or a nut isn’t tight enough. The fuel petcock and carburetor are the most common places that a motorcycle lets out gas. You can click here to read my article on this subject.

What happens if my motorcycle has an oil leak? While occasional rides with an oil leak won’t cause any damage, consistently riding with a leak without addressing the issue could eventually cause the engine to seize because of the lack of oil inside the engine.

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