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8 Most Common Problems with Kawasaki Jet Skis [Video]

8 Most Common Problems with Kawasaki Jet Skis [Video]

It’s safe to say that the eight most common problems with Kawasaki Jet Skis are as follows:

  1. Limited availability
  2. Engines are hard to work on
  3. Belt-driven supercharger
  4. Cylinder head and pump bearing issues (on 250/260 models)
  5. Lack of a bilge pump and shut-off valve
  6. Electrical failures and loose connections
  7. Lack of innovation
  8. Cavitation and overheating
If you want to learn more about these issues, you’ve come to the right place.

We at JetDrift have compiled the most common problems with Kawasaki Jet Skis under one roof!

8 Most Common Problem With Kawasaki Jet Skis

Kawasaki Jet Skis are amazing machines with a very long history. But just like any other machine, these have specific problems and issues that require extra attention.

Let’s drill into the details and talk about them one-by-one!

1. Limited Availability

Comparing the “Big Three” PWC manufacturers – Yamaha, Sea-Doo, and Kawasaki – we find that the latter has a significantly smaller market share.

Each year, the market leader is Sea-Doo, with a market share of about 54-55%, while Yamaha typically has about 39-40%. A simple calculation shows that Kawasaki’s market share only ranges from 5-7%.

You are probably wondering why Kawasaki Jet Skis are seemingly so unpopular.

One of the main reasons is limited availability. To the greatest regret of many Kawasaki fans, the company has a significantly smaller dealer network in the U.S. compared to its competitors.

This means that buyers have less opportunity to check out and test-ride these machines.

Sure, jet skis can be delivered over long distances, but they still have to be taken to dealers for warranty and other repairs.

Warranty and yearly repairs can cause many headaches if the dealership is located far from the owner!

2. Kawasaki Engines are Hard to Work on

Due to their design, Kawasaki engines are harder to work with than Rotax (Sea-Doo) or Yamaha marine engines.

This drawback makes Kawasaki Jet Skis more difficult to service, resulting in higher labor costs. What’s more, they are harder to repair at home, which can be a disadvantage for those who prefer to do the maintenance themselves.

3. Belt-Driven Supercharger

Unlike the rival supercharged models, Karawaskis feature a belt-driven supercharger.

As you can imagine, this drive belt wears out fast and requires regular inspection and maintenance. This system also utilizes a tensioner, which is prone to seizing due to corrosion.

Therefore, the supercharger on Kawasaki Jet Skis requires continuous attention and care.

The belt typically starts having signs of wear after 70-100 hours, depending on a multitude of factors. As a result of wear and tear, the belt can spray black rubber particles into the engine compartment.

Another obvious sign of wear is when the ribs break off, or the white reinforced braiding appears on the edge of the belt.

These are considered the most common indicators that it might be time to replace the belt.

The tensioner also has to be periodically disassembled, cleaned, and greased to extend the belt’s life. It also makes sense to keep the engine compartment dry to avoid corrosion on the tensioner.

Besides the belt and the tensioner, the supercharger can also go wrong in many ways, resulting in a massive repair bill. What’s more, the extra power provided by the supercharger makes the entire engine less reliable.

So, if you are looking for a reliable Kawasaki Jet Ski, it’s recommended that you steer clear of the supercharged models!

4. Cylinder Head and Pump Bearing Issues (on 250/260 models)

The early supercharged Kawasaki Jet Skis had a bad reputation for low reliability and durability, and with good reason.

The Japanese manufacturer introduced its first supercharged model, the Ultra 250X, in late 2006, followed by the more advanced 260X. Unfortunately, these models suffered from cylinder head and pump bearing issues.

Many owners reported serious engine damage at low hours caused by broken or cracked cylinder heads.

Another common issue on these models was jet pump bearing failure. Kawasaki used sealed bearings in these pumps, which they claimed were “maintenance free” since there was no way to grease them.

But unfortunately, these bearings were prone to failing after 70-100 engine hours. A seized bearing could lock up the drive shaft causing various types of damage to the impeller, driveshaft, and/or pump housing. Unlike Sea-Doos, Kawasakis don’t feature a wear ring, so the entire pump housing has to be replaced in case of damage.

In a worst-case scenario, a locked drive shaft can transfer thrust onto the crankshaft, resulting in a blown engine. Due to this risk, the pump has to be rebuilt on these Jet Skis every 100 hours or every season.

Therefore, if you want to prevent these issues, best practice is to avoid buying used supercharged Ultra 250 and 260 Jet Skis. These models were manufactured from 2006 through 2011.

If you are considering buying a used Kawasaki Jet Ski, best practice is to stick to the naturally aspirated models. These are always a better deal as their engines last much longer and carry much lower risks of a malfunction.

But if you want to buy a used supercharged Kawasaki Jet Ski, by all means, you should take a look at the Ultra 300 or 310 models (2011 and above).

Fortunately, the cylinder head and pump bearing issues were resolved in the 2011 Ultra 300!

5. Lack of a Bilge Pump and Shut-off Valve

Despite its importance, most Kawasaki Jet Skis still come without an electric bilge pump. Instead, they often utilize a bailer that uses the jet pump’s suction to drain the bilge water.

Since the bailer solely relies on the vacuum generated by the jet pump, it only works effectively when the machine is running at higher speeds. This means that if the ski is tied to a dock, only a small water leak can cause it to sink!To avoid this issue, installing an aftermarket electric bilge pump is highly recommended for all Jet Skis!

The other important part missing from Kawasaki Jet Skis is the shut-off valve.

This simple ball valve is a must for high-speed towing, so it’s a mystery as to why it is not standard equipment on every PWC!

6. Electrical/ECU Failures

As we know, electricity and water don’t mix well. This is why a vessel’s electrical system is prone to failure, and Kawasaki Jet Skis are no exception.

Since the hull of these machines is not completely waterproof, water finds its way to electrical systems and the engine.

The presence of water inside the hull often causes corrosion on the wire harnesses, fuses, relays, sensors, and other electrical units.

Even if rust doesn’t attack them, wiring harnesses, battery terminals, and hose connections can loosen over time. Rubber lines are also prone to ripping or falling off the nipples causing various malfunctions.

The ripped/loosened oil lines are common problems on 2-stroke oil-injected Jet Skis, often resulting in an engine seizure.

(Due to this risk, the oil hoses must be periodically replaced on every oil-injected, 2-stroke Jet Ski!)There’s also a main computer (ECU) in each Kawaski Jet Ski intended to control the engine and the systems. And just like any other electrical feature, this “brain” can also go wrong in many ways.

Only a little malfunction in the electrical system or the ECU can prevent the ski from starting or put it into a “limp mode,” which restricts the engine to a lower speed.

7. Lack of Innovation

Let’s face it, Kawasaki Jet Skis are not known for having innovative features since the Japanese manufacturer lags behind its competition in many areas.

For example, Kawasaki released its brake and reverse system on their flagship models in 2021. In contrast, this system has been available on competitor models for many years.

To be more precise, manufacturers released their braking systems in the following years:

  • Sea-Doo iBR: 2008 (for the 2009 model year)
  • Yamaha RiDE: 2014 (for the 2015 model year)
  • Kawasaki KSDR: 2021 (for the 2022 model year)
Also, let’s see when these manufacturers revealed their first supercharged models:
  • Sea-Doo: 2003 (GTX 4-TEC Limited)
  • Yamaha: 2008 (FX SHO)
  • Kawasaki: 2011 (Ultra 250X)
As you can see, Kawasaki is usually in no hurry to keep up with the competition!

The manufacturer has also used the same engines for pumps for many years, without any significant changes.

For example, the Kawasaki STX-15F was revealed in 2003, and two years later, it received a 1,498cc, 4-stroke DOHC engine. This model remained virtually unchanged until 2020 when it got a new top deck and was renamed the STX-160.

But aside from its deck and some new features, the hull, engine, and pump were carried over to the new model without any changes. Therefore, the “new” STX-160 family utilizes nearly 20-year-old technology offering the same performance and riding experience as its predecessors.

You can also find the same engine and pump in the stand-up SX-R 1500 and the naturally-aspirated Ultra LX models.

Although the redesigned flagship Ultra 310 line got an entirely new body and some new features for 2022, the engine and the propulsion on these skis were inherited from their predecessors.

Therefore, it’s safe to say that supercharged Kawasaki Jet Ski engines have been basically unchanged since the early 2010s.

8. Cavitation and Overheating

Due to their design and complex systems, PWCs are known for frequent overheating issues.

This malfunction is typically caused by a clogged cooling system or a defective heat sensor.

Kawasaki Jet Skis utilize an open-loop cooling system that uses external water to cool down the engine and other parts like the exhaust and the intercooler. The drawback of this design is that salt build-ups or debris can clog the system, causing the Jet Ski to overheat.

(To prevent these issues, these systems must be flushed out after each ride.)Overheating can also be caused by cavitation, which is another common issue on jet-propelled vessels. There could be many reasons why a Jet Ski cavitates, but the most common ones are as follows:

You can read more about these issues by following the links above.

This is our short compilation of the most common problems with Kawasaki Jet Skis, we hope you find it useful!