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Are you wondering how much water to hydrolock an engine? Well, it’s worth noting that even a half cup of water is enough for an engine to hydrolock. Most times, it doesn’t take too much amount of water to hydrolock and engine (more on this later).
Hydrolocking is when too much water flows into the combustion chamber of an engine. Somehow, this is easy to occur because there are many scenarios that cause water to enter the engine bay.
Basically, there’s nothing wrong with water getting into your engine bay – in fact, you can wash your car’s engine bay whenever you think it’s dirty. But then, there are specific components that are allergic to water – they shouldn’t get wet.
These water allergic components include fan belts, electrical components, and cylinders. Since water cannot be compressed, when it’s ingested by the cylinders, it can cause the engine to lock, and this can lead to costlier damages.
What Happens When a Car Gets Hydrolocked?
Depending on your speed level when the hydrolocking happened, the damage could be repairable or irreparable. If you were driving at a great speed, a couple of components might break or bend when hydrolocking occurs.
These components that may be affected include the connecting rod, crankcase, valves, bearings, and engine blocks. In worse scenarios, your engine could get totaled instantly.
How Much Water To Hydrolock An Engine?

Okay, it is obvious that water can hydrolock an engine, but what quantity of water would it take for that to happen? Apparently, if you drove through the rain for some hours, water must have penetrated your engine bay.
However, water penetrating the engine bay does not imply that your engine is immediately at risk. It takes a certain amount of water for an engine to get hydrolocked.
Well, a certain amount of water is just “a cup full.” Yes, if what seems like a cup of water gets into your engine and gets ingested by the cylinders, your engine will get hydrolocked.
More so, some mechanics say that even half a cup of water is enough to hydrolock an engine. Sounds bad? Yes, it doesn’t have too much water to hydrolock an engine, but, well, there is a way to get around an hydrolocked engine.
It is important to iterate that hydrolocking can wreck an engine completely. If you’re lucky to have a hydrolocked engine that isn’t yet totaled, you can fix things up, and remember to take precautions against such a scenario again.
Furthermore, it is important to note that getting stuck in traffic when there’s a downpour does not guarantee that your engine could get hydrolocked. Yes, drops are not enough, what seems like a cup full of water needs to run into the cylinders at a go for it to get hydrolocked.
However, if you drive through high waters, your car will be submerged, and that can cause hydrolocking. Some cars have their intake system close to the wheels; such cars can get hydrolocked when you drive through high-waters.
Now, let’s quickly look at some of the notable hydrolocked engine symptoms to always look out for!
What Does a Hydrolocked Engine Sound Like?
How would an hydrolocked engine sound? It’d sound awful – you’d hear a loud knocking sound as you drive.
This noise would not sound for long; typically, it’d go on for a few seconds, and next, your engine would shut off.
How To Tell If An Engine Is Hydrolocked (Hydrolocked Engine Symptoms)

What are the signs of a hydrolocked engine? The most common sign is that you’d start hearing serious noise coming from the engine bay. Well, there are pretty many symptoms of an hydrolocked engine, and they are explained below.
1. Engine Stalling
Engine stalling is a common sign of a faulty engine; once something is not right with your engine, it’d start to stall.
So, if you drove through high-waters, and then your engine starts to stall, it could be a potential hydrolock situation.
2. Engine Not Turning Over
When you notice that your car is no longer functioning at ease after you drove through a downpour or high water, it could be a potential hydrolock situation.
Usually, when an engine hydrolocks at idle speed, it would stop turning over.
3. Sputtering
Sputtering means slight shaking. So, engine sputtering refers to the slight shaking of your car as you drive. Yes, if water gets into the cylinders, it can cause this to happen.
4. Unusual Noise
Another common symptom of hydrolocking engine is knocking or hammering noise from the engine bay. You’d notice that your car makes a serious unusual noise as you drive – especially when you try to accelerate.
When you start experiencing any of these four signs, you should check for water in your engine right away.
What Else Can Cause Hydrolocking?
We’ve been mentioning water as what causes hydrolocking. Yes, that is true, but the coolant in your car can also cause hydrolocking. The coolant liquid can get into the cylinders; thus, causing hydrolocking.
Well, the coolant liquid cannot just get into the cylinders; such a scenario can only occur when there is a mechanical failure like a damaged head gasket.
That said, when your car’s head gasket is faulty or damaged, it can allow the coolant liquid to overflow into the cylinder; hence, causing hydrolocking. Remember, the cylinders do not need to take in too much liquid to get hydrolocked.
Will a Hydrolocked Engine Turn Over?

Interestingly, we had mentioned this as one of the signs/symptoms of a hydrolocked. Apparently, an hydrolocked engine would not turn over.
So to say, a hydrolocked engine won’t crank or start. If you force this, you may end up totaling the engine.
Can You Fix a Hydrolocked Engine?
If the damage is not too severe (and the engine is not yet totaled), you can fix a hydrolocked by replacing the affected engine components. Generally, fixing a hydrolocked engine implies dismantling the components, including the cylinder.
When you’ve dismantled them, then you can take time to remove the moisture and water inside. Make sure the parts are dry before reassembling them.
Notwithstanding, if the water has stayed for long inside the engine, chances of reviving such an engine are very slim.
What More?
To prevent your engine from getting hydrolocked, you should not drive through puddles (high waters), instead, go around.
Also, if you got stuck in traffic and there’s a heavy downpour, when you get home, ensure to check your engine and dry out water from the engine bay. Hopefully, these tips are what you seek.