What Is A Hydrolocked Engine And How Do You Fix It? [2024]

Aspiration is that coughing and choking feeling you get when food or liquid goes down “the wrong pipe.”

Something similar also occurs if too much water enters your engine, it’s called hydrolock, and it can disable your vehicle!

What is a hydrolocked engine, and how do you fix it?

Engine pistons are designed to compress a mixture of air and fuel – not water. Because of this, if adequate water enters the cylinder, it may hydrolock, meaning they all stop moving at once.

Much of the resulting damage depends on how quickly you were going when it happened.

Fortunately, in this guide, I will elucidate all the crucial information about a hydrolocked engine. This also involves what causes an engine to hydro lock, if it can result in damage, and how to rectify it.

Are you ready to get started?

Let’s plunge right in!

Table of ContentsShow

What Causes An Engine to Hydrolock?

driving in water — Do not drive through puddles, as it may cause a hydrolocked engine.

The actual term is Hydrostatic Lock, which has been abbreviated to hydrolock. This occurs when abundant water enters the combustion chamber.

When a piston reaches the peak of its travel range, if the volume of water inside is more than the amount of space left, hydrolock will occur.

Why? Because water is less compressible than the air/fuel mixture inside. So, when the piston tries to compress it, all of the cylinders will stop at once.

This will result in crashing or clattering sounds inside the engine that will last several instants, followed by it shutting down.

What kind of situation can result in water entering the cylinders? There are many examples, like driving in a heavy downpour or going through a deep puddle. This is one of the reasons that flood-damaged vehicles are often totaled afterward.

It’s also possible for the hydro lock to occur from other fluids, like oil or coolant. However, remember that if this happens, it likely means you have a substantial issue inside your engine, like a blown head gasket or a crack in the block.

Does Hydrolocking Harm An Engine?

Hydrolock can be exceedingly detrimental to an engine and may require its replacement entirely. However, the velocity you were going is what typically determines the magnitude of the damage.

While the RPMs are low, such as when you’re idling or progressing slowly, only a small amount of water may enter. In this case, you need to act swiftly to remove it before it causes corrosion issues.

If you were going rapidly when the hydrolock occurred, where the RPMs were high, serious damage might occur.

A pair of these consist of:

A bent or broken connecting rod
A breach in the head
Crankcase damage
A bent valve
Damage in the bearings
Piston ring damage
Harm to the block

When associating the words “metal” and “water,” the initial thing most of us ponder is rust. This is precisely the situation with hydrolock.

If you don’t act promptly to remove the water, your engine will rust, which will likely render it useless.

How To Fix A Hydrolocked Engine

Whether a resolution is feasible depends on the amount of water that has entered, as well as how long it’s been there.

If you were moving at a sluggish rate of speed when the RPMs were low, you might be able to clear the system of water by yourself.

This involves removing the spark plugs, starting the engine, and then revving it while it’s in park. You should notice water spewing out of one or more cylinders. You should also replace the spark plugs with new ones. Though, in an urgent situation, you should be able to just dry yours off.

It is crucial to wipe the cylinder walls to get rid of dampness that may cause damage. However, if a secured area is not available, the cleaning can be done later.

The other possibility is that there’s a significant amount of water inside your engine. In this case, there’s really nothing you can do other than salvage what you can and replace the rest. In a worst-case scenario, a hydrolocked engine can cost anywhere between $3,000-$8,000.