Nothing quite beats the freedom and exhilaration you get from taking a jet ski out for a ride on a hot summer’s day, especially with that fountain of water shooting and spraying up in the air. But hang on… why exactly do jet skis spray water up? If you’ve ever wondered, here’s the correct answer.
Why do jet skis shoot water up in the air? The water you see spraying up from the back of a jet ski happens for two reasons. It will either be from a visibility spout so other boaters can see you, or it will be a release of water that has been used to cool the engine.
That’s the simple answer, but just like with any high-powered machine, the more you know about how it works, the safer you will be.
So why did I give you two reasons for the water shooting up from the back of a jet ski? Well it’s simple actually and is down to the brand and design. I will go into both reasons for why jet skis spray water up below.
Reason 1: Visibility spout on Yamaha jet skis
If it’s a Yamaha jet ski, the fountain of water you see spraying and shooting up in the air from the rear will be exiting via a visibility spout.
This piece of functionality has been designed for safety.
Jet ski accidents are common, and one of the biggest causes of injury are collisions. Collisions on the water can happen for many reasons, including your own recklessness, but also that of other water users.
Yamaha decided to add the visibility spout to their jet skis and PWCs as a safety feature. The thinking behind is that with a mesmerizing plume of water shooting off the back of the jet ski, it would make the rider more visible to boats and other risks.
The visibility spout runs off the thrust generated by the impeller. It re-directs some of the water that comes out of the jet ski pump, and then pushes it up a tube that is set vertically behind the rider. You can see an example of this in action in the photo below.
The Yamaha visibility spout is able to shoot and spray water up from the jet ski to a distance between 10 and 15 feet high.
Experienced jet skiers have mixed feelings about the Yamaha visibility spout. From reading boating forums, the general consensus seems to be split as to whether they are popular or not.
In fact, some jet skiers hate the way water shoots out of the back of their Yamaha Wave Runner jet ski and disable the functionality altogether.
I actually read some disparaging remarks about the Yamaha visibility spout from experienced jet skiers, with nicknames for it such as “vertical p*sser” and the “gay spray”.
Here’s a few reasons for either stopping the jet skis shooting water up or keeping them in place. I read the comments below on some web forums whilst researching this topic.
“When I had a Yamaha PWC, I actually disconnected the visibility spout. I just didn’t like the attention it drew to me when riding, and I always seemed to get soaked by it.”
“I actually like the water spraying up from my Yamaha jet ski. In my opinion, anything that makes it less likely for me to get hit by someone who is not paying proper attention to the water is a good thing.”
“In my opinion they don’t offer that much more visibility. The only time I can see the visibility spout spray being useful is if you were jumping waves a lot, where your visibility is reduced.”
If you are in the camp of people who don’t like to see water shooting off the back of your jet ski, then you can quickly disconnect it. It takes around 10 seconds to do, and you just disconnect a small hose that’s clipped into the exit nozzle.
Did you know? Yamaha have actually patented the visibility spout, so you won’t see water spraying up on another brand for the same reason, only on Yamaha Wave Runners.
Reason 2: Engine cooling system
Kawasaki invented the term “jet ski” in the 1970s, and you can read more about the history behind them here. That blog post also includes a few key dates on the history of PWC and jet ski popularity.
On Kawasaki models, their jet skis shoot water up in the air to cool down the engine. As the jet ski flies through the water, the engine will suck water up into a vent underneath and then shoot it out the back.
When the water gets pulled into the jet ski, some of it will pass over the engine into the water-cooling system. In many Kawasaki models, the used water will then be expelled from the side. Other brands of jet ski shoot the cooling water out the back in a plume sometimes between 4 to 5 feet high.
By having the water spray out of your jet ski, you have the peace of mind in knowing that the engine is being cooled down and there are no blockages in the water-cooling system.
With some jet skis, the manufacturer will funnel the cooling water in an arc from the back purely for cosmetic reasons – as it can look very cool. Like I said though, with others including the Sea Doo brand it will just be a tiny hole that doesn’t shoot large arcs of water.
Are jet ski water sprays dangerous?
No, they aren’t. But they can be annoying and can get other people very wet who might not appreciate it. Here’s a few stories from experienced jet skiers who have gotten themselves or other people soaked with the water spray.
“I’m always very cautious when I see Yamaha jet skis being unloaded at the ramp. Only last month I stood to close to one that managed to shoot a load of water into a fountain that landed right on me, completely soaking my iPhone”
“I hate Yamaha riders. One of them almost soaked us last year when we were pulling our pontoon boat out of our local marina. It’s almost like he did it on purpose! He thought it was funny… we didn’t.”
“Water spray can soak the rider if the wind is facing in the wrong direction and you’re driving at superfast speeds. You can get sprayed by your own water jet. I’ve done it a few times.”
“It can be a problem if you’re riding in a larger group of jet skiers. If you think it will affect you, just disconnect the visibility spout and you’re good to go. Simples. Take no time at all.”
“My buddy and I jet ski on a bay and the ones with Yamahas always get a good soaking if there’s an easterly wind blowing as we head back into the bay in the no-wake zones. The trick is to not ride next to them if you want to talk and not get wet!”
Next time you’re on the water or at the beach and someone asks you why do jet skis shoot water up in the air, you’ve now got the answer!
It will either be because it’s a Yamaha running with a visibility spout, or a different brand of jet ski and PWC that is using a spray to dispel the excess water used for engine cooling.
Either way, everyone else on the water should see the jet ski coming with a large arc of water being sprayed. Whether it’s a safety or functional feature, it’s worth keeping running just to be on the safe side.
Did you know: The top production jet skis can have top speeds of nearly 70 miles per hour!