Why Do Jet Skis Explode ?

The high adrenaline of skidding through ocean waves at high speed is thrilling to most people, and that’s what jet skis do. While they may not seem inherently dangerous, knowing the risks of jet skis exploding is vital.

Jet ski explosions are mainly caused by a build-up of fumes in the gas chamber which is ignited when it is started. This is usually a result of poor maintenance or careless riding resulting in damage.


Why a Jet Ski Explodes

Jet ski explosions occur mainly after the build-up of fumes in the gas chamber is ignited by a spark. The result is almost always fire or a massive explosion that can extend depending on where it explodes.

In fact, you’d be surprised that jet skis can also explode at the shore, sometimes even during the first ignition. Such cases happen when the blower assembly isn’t taken care of, causing a malfunctioning engine.

Due to these risks, the ownership of jet skis is very strict, and the jet ski must be insured, licensed, and subject to regular maintenance.

What Causes A Jet Ski Explosion ?

Like any vehicle with a combustion engine, jet ski explosions happen more often than we think. Let’s look at some of the leading causes of jet ski explosions.

Poor Ventilation

Unlike big boats, jet skis do not have a huge ventilation system as it relies on a passive ventilation system.

So, what is a passive ventilation system?

Jet skis achieve ventilation through two 3 sq. in. openings located on opposite ends at the aft or fore of the engine compartment. Since it is not an active ventilation system, it needs wind to blow air through the holes and remove any accumulated gas vapors.

So, the jet ski becomes dangerous in stationary motion as there is no wind to blow out the combustion vapors. Jet skis owners must switch on this fan at least five minutes before starting it.

It would be a nice safety feature if they installed bilge blowers in a jet ski, but it is not as common in the US.

Poor Maintenance

Any issue of improper jet ski maintenance has to do with the combustion engine and the electric system. If you fail to take care of the engine, you could quickly end up in hospital.

The engine compartment does a lot of mixing, and when gas vapors accumulate, anything that can spark results in a huge jet ski explosion. Of course, the sparks won’t come from you lighting a cigarette- the electrical system often causes it.

Jet skis have their electrical systems sealed to prevent corrosion, moisture, or contact with other electrical components. However, not all parts are sealed, and places like the battery terminals and solenoids are exposed.

These parts can spur an explosion once there is enough accumulation of gas vapors in the hull.

The gas vapors may leak due to a holed gas tank, faulty gasket, broken interior parts, and other faults from poor maintenance.

Nevertheless, lack of oil and poor cooling may also result in malfunction or, worse, explosion. The risks are higher if the jet ski is older since the old versions of jet skis have many holes, increasing the chances of vapor leakage.

Every jet ski needs proper maintenance, and as an owner, you might want to assess your engine every time you go out for a ride. Refer to your product manuals for guidance.

Performance modifications

Another potential cause of jet ski explosions is modifications and high-performance engines. The high-performance engines have powerful thrust and can go as high as 300 HP.

If you keep pushing your engine to top speeds, you constantly expose the components to stress, potentially cultivating a breakdown. So, to keep things safe, ride slower, and if you need to go fast, don’t ride for too long.

Also, avoid any modifications intended to increase the performance of the jet ski. Anything from turbochargers, air intakes, speed control modules, pump components, or installation or racing kits.

If you must make modifications, ensure you use industry-standard parts and meticulous installation.

How To Prevent Jet Ski Explosions

Even with preventive measures in place, jet skis can still explode. You must constantly check for faults before every ride and ensure everything is functioning properly. Follow these steps to ensure your jet ski is in optimal performance, especially in the hull.

  • Carefully read the owner’s manual and refer to it when you feel you need information about something. Please avoid DIY fixes for a problem particularly related to the engine- always use your manual or a jet ski expert.
  • Ensure the “pre-ride” checklist is the first thing you do before going on a ride. It is the single most crucial section that will reduce the risk of explosion.
  • Always ensure the jet ski is well-maintained to increase its lifespan and avoid unnecessary accidents. Some things to look at include oil, fuel lines, cooling, and electric systems.
  • Before starting, always remove the seat and look for signs of leakage, such as gas vapors. Please note that removing seats on old models may be tricky, although the two parts are still removable.

Personal Safety

Although we can do much to avoid jet ski explosions, we still can’t completely rule out the possibility of it happening. Yes, sometimes bad luck happens!

So, to avoid many injuries, you may need to take responsibility for your safety. These measures can make a safer ride and prevent damage in case of an accident or explosion.

Life Jackets

The life jacket to use will depend on the various regulations stipulated by your country or state. However, it is vital to wear a properly fitting life jacket for every passenger on the jet ski. Most explosions result in passengers being thrown off several meters away and drowning.


Helmets are generally not on the requirement list, but they are better at increasing safety and protecting from head injuries. Helmets also serve as good camera holders or goggles so you can record while on the move.

Lower body clothing

Due to the risk of falling injury, wearing a wetsuit or neoprene shorts is recommended. You can choose from a wide variety; besides protection, they’ll keep you warm during winter.

Other gear

Apart from the above items, most states also require that you bring the following on board

  • Registration documents
  • Fire extinguisher
  • Sound signaling device


Though there are strict rules for owners, acquiring a license to drive a jet ski is not a legal requirement. It is wise to get training before jumping on a jet ski to avoid putting yourself or anyone near you at risk.

Many online training modules and classroom offerings teach how to ride a jet ski properly. The requirements for who needs a boating license are offered by the state and may vary.

Frequently Asked Questions

How many jet ski deaths are there in a year ?

According to the U.S Coast Guard Accident Statistics, roughly 40 to 50 people die yearly due to jet ski-related accidents. Also, 600-700 injuries are reported related to jet ski accidents and explosions.

Do jet skis have blowers ?

Jet skis do not require blowers as they have a passive ventilation system consisting of two openings. The system relies on wind to blow out any gas inside the chamber.

What type of fire extinguisher do you need for a jet ski ?

A type B fire extinguisher. The Federal law states that all PWCs, including jet skis, have a type B fire extinguisher if one or more of the following exists; closed compartments where fuel tanks may be stored and any inboard engine.

Scroll to Top