Does auto insurance cover hydrolock?

Auto insurance does cover a hydrolocked engine under certain circumstances, but companies can deny your claim if neglect or misuse is proven. Learn how to make sure you're covered for this situation.

Free Auto Insurance Comparison

secured lock Secured with SHA-256 Encryption

Rachel Bodine graduated from college with a BA in English. She has since worked as a Feature Writer in the insurance industry and gained a deep knowledge of state and countrywide insurance laws and rates. Her research and writing focus on helping readers understand their insurance coverage and how to find savings. Her expert advice on insurance has been featured on sites like PhotoEnforced, All...

Full Bio →

Written by Rachel Bodine
Feature Writer Rachel Bodine

Dan Walker graduated with a BS in Administrative Management in 2005 and has been working in his family’s insurance agency, FCI Agency, for 15 years (BBB A+). He is licensed as an agent to write property and casualty insurance, including home, auto, umbrella, and dwelling fire insurance. He’s also been featured on sites like and Safeco. He reviews content, ensuring that ex...

Full Bio →

Reviewed by Daniel Walker
Licensed Auto Insurance Agent Daniel Walker

UPDATED: Jun 7, 2022

Advertiser Disclosure

It’s all about you. We want to help you make the right coverage choices.

Advertiser Disclosure: We strive to help you make confident auto insurance decisions. Comparison shopping should be easy. We are not affiliated with any one auto insurance provider and cannot guarantee quotes from any single provider. Our partnerships don’t influence our content. Our opinions are our own. To compare quotes from many different companies please enter your ZIP code on this page to use the free quote tool. The more quotes you compare, the more chances to save.

Editorial Guidelines: We are a free online resource for anyone interested in learning more about auto insurance. Our goal is to be an objective, third-party resource for everything auto insurance related. We update our site regularly, and all content is reviewed by auto insurance experts.

Things to remember...

  • Only a comprehensive insurance policy can cover your vehicle in the event of hydrolock
  • An insurance company could deny your claim if the damage occurred due to negligence or misuse
  • Hydrolock happens when too much water gets into the cylinders in your car engine 

When it comes to your car, any mechanical malfunction or failure is cause for concern, and it’s worth knowing whether your policy can cover a hydrolocked engine insurance claim.

Unless you have comprehensive insurance, you likely are not protected from hydrolock damage. Your coverage can also depend on the cause of the damage since many companies have exclusion policies.

Hydrolock repairs can be expensive, and in severe cases, you might need to pay for a complete engine rebuild or replace your vehicle entirely. This article will help you understand how hydrolock can occur, which types of insurance cover it, and why your policy might not pay out.

Does my insurance cover hydrolock?

If you have concerns about your vehicle, you should know whether your policy covers hydrolock. Most car insurance fits into the three categories of liability, collision, and comprehensive coverage:

  • Liability. Liability insurance pays for collision damage and bodily injury from a collision where you are at fault.
  • Collision. Collision insurance covers the cost of any damage to your vehicle caused by someone else during a collision.
  • Comprehensive. Comprehensive insurance covers a wide range of non-collision-related damage.

Only a comprehensive auto insurance claim can protect you in the event of a hydrolocked engine. While liability and collision insurance policies only protect against damages related to a traffic collision. Since a hydrolocked engine is almost always a mechanical issue, these policy types generally cannot cover your engine insurance claim.

Free Auto Insurance Comparison

Enter your ZIP code below to view companies that have cheap auto insurance rates.

secured lock Secured with SHA-256 Encryption

When can a company deny my hydrolocked engine insurance claim?

Even with a policy covering engine damage, your insurance company could deny your claim if your coverage comes with exclusions. Most companies include exclusions to avoid paying out on potentially fraudulent claims or for damage directly caused by the policyholder.

The most common exclusions involving hydrolock are neglect and misuse. If your insurance company determines that your claim falls into either category, you could have to pay the entire cost for repairs. Understanding your policy and its exclusions can help avoid unwanted outcomes.


Insurance companies consider neglect as any failure to act that results in damages to your vehicle. An engine that becomes hydrolocked due to a lack of proper maintenance or preventative services could be your responsibility to repair.

Even with weather-related damage coverage, your policy might not protect you if you left your vehicle parked with its windows or sunroof open ahead of a rainstorm or hurricane.


If your insurance company determines that your hydrolocked engine was due to your misuse of the vehicle, the insurance company could deny your insurance claim. Examples of misuse include attempting to drive your car through standing water during a flood or modifying your vehicle in ways that leave it vulnerable to damage.

A hydrolocked engine is an expense that your policy might not cover, but it’s often preventable if you take proper precautions and exercise caution and good judgment.

What is hydrolock?

Hydrolock, or hydrostatic lock, is a mechanical failure caused by excessive water or other liquid getting into your engine and causing it to seize. Pistons within the cylinders compress air as part of the internal combustion reaction that powers your vehicle. When fluid starts to fill this small space, it can prevent them from functioning.

Based on how fast your car is going when the engine fails, the force of a sudden seizure can lead to bent or broken rods or cracks in the engine block. Depending on the extent of the damage, this can make your vehicle completely inoperable. Understanding how this can occur helps you recognize when your car could be at risk.

What causes hydrolock?

The most common causes of hydrolock involve exposure to large amounts of water, typically during a hurricane, flash flood, or severe rainstorm. Water can get into your engine through its air intake, which sits lower on some vehicle models than others.

In addition to high water levels and heavy rain, coolant might get into your cylinders if there is a crack or leak in need of repair. A damaged carburetor or fuel injector can also potentially result in excess fluid, leading to a hydrolocked engine if left unaddressed for too long.

Many common causes of hydrolock are preventable, but if your car sustains severe damage, it can result in expensive repairs.

How much does it cost to repair a hydrolocked engine?

With any significant damage to your engine, you could be looking at a substantial amount of money for repairs. Depending on the extent of the damage, you might have to pay to replace the entire engine, which costs thousands of dollars.

In the most severe cases, there could be damage to other systems in your car, which means the repair cost could exceed the total value of your vehicle. Having the right coverage helps protect you from shouldering the burden of a costly repair.

How can I prevent hydrolock?

If you live in a city that experiences severe water-related weather, your car is at a greater risk for hydrolock, especially if your area floods.

You can help protect your vehicle by storing it in a garage or covered parking above sea level and exercising caution during flood conditions. Avoid driving through floodwaters, regardless of their apparent depth.

Since mechanical issues can also lead to hydrolock, keep your car well-maintained and get any repairs done before they have a chance to become a bigger problem. In many cases, this is avoidable, so be proactive and exercise good judgment.

Free Auto Insurance Comparison

Enter your ZIP code below to view companies that have cheap auto insurance rates.

secured lock Secured with SHA-256 Encryption

Final Thoughts on Hydrolock Coverage

Hydrolock is a major mechanical malfunction resulting in an inoperable vehicle and high repair costs. It is worth understanding what causes hydrolock, how to prevent it, and which insurance coverage can protect you if it happens to your car.

Free Auto Insurance Comparison

Enter your ZIP code below to view companies that have cheap auto insurance rates.

secured lock Secured with SHA-256 Encryption