I want to do a post on the wear ring, it’s purpose, and the symptoms of a damaged one.
The wear ring can be a love-hate relationship but serves an important role in protecting your watercraft. Let’s go over it and why it quite an amazing at protecting your jet ski.
The Purpose Of The Wear Ring
The reason why Sea-Doo uses a plastic wear ring is to protect the PWC from any major damage that might come from sucking something up.
The Sea-Doo wear ring is simple, it’s a thick piece of plastic that wraps around the impeller. The gap between the impeller and the wear ring is very tight because it needs to be to give you the correct propulsion.
With tight tolerances between the impeller and wear ring, anything that gets sucked up into the pump can damage either one. It’s more likely to damage the wear ring, but big and hard items like rocks can also damage the impeller.
Without the wear ring, your jet pump would take the damage, and it’s much larger and more expensive to fix.
How To Know Your Wear Ring Is Damaged?
The symptoms of a damaged wear ring is a lack of power even though the engine RPMs are fine. The jet ski will feel like it has all the power, but just won’t “catch” and take off.
Many people confuse a damaged wear ring with other things, like thinking the transmission is damaged or not catching. You give it gas, but the jet ski “won’t shift” is a common saying. Jet ski’s do not have transmissions, if the engine is on the then impeller is moving.
The forward and reverse are done by moving a bucking up and down to redirect the thrust.
The slipping or not feeling like the engine is catching until later is because the wear ring has a groove(s) cut into it. The groves allow water to escape around the impeller instead of through the impeller. This makes the PWC feel like it wants to take off, but you’re just not moving that much.
Many things can cut groves into your jet ski’s wear ring, such as rocks, sticks, sand, and more. It’s usually the small things that cut the groves and then get forced out. The groves might not be noticeable until you take the jet pump off.
Note: it’s normal for the impeller to cut a few groves into the wear ring itself as it gets broken-in. These groves won’t affect take off unless the impeller is damaged. It’s the large and improper groves that are the issues.
How Often To Replace A Wear Ring
Unlike the name “WEAR” ring, it’s not something that needs constant maintenance or replacing.
The only time the wear ring needs replacing is when it’s damaged from sucking something up. There is no need to replace the wear ring every so often, it’s best you don’t touch it until it’s damaged.
Once the wear ring is damaged, you must replace it or your jet ski won’t be the same until it’s fixed; the problem doesn’t “work it’s self out”.
How To Replace Sea-Doo Wear Ring
The process for replacing the wear ring is different for every model of Sea-Doo. Some are super easy, like the Spark’s without iBR, and others are a lot harder.
The video below I really like and shows how to replace a wear ring on a modern 4-stroke Sea-Doo.
Plastic Vs. Stainless-Steel Wear Ring
I know, a plastic wear ring doesn’t seem as ideal compared to something that is harder and stronger, like a stainless-steel wear ring.
You can buy replacement wear rings for your Sea-Doo that are stainless steel, but I suggest you don’t.
The goal of the wear ring is to protect your jet pump, and more importantly, the impeller. The impeller is metal, and the wear ring being plastic means it takes the abuse and not the impeller. If the wear ring is metal, then it’s the weaker of the two metals that will get destroyed and that is often the impeller since it takes more abuse by micro-cavitation.
The wear ring is meant to be the thing that gets sacrificed, and not the more expensive items like the impeller. The average jet ski owner is better off with a plastic wear ring, unless you race, then it might be slightly better to get metal.
How Often To Replace Jet Ski Impeller
Every year or 100 hours, you should have your jet ski’s impeller inspected to see if it needs to be replaced. Most dealerships will do this inspection as part of your service.
The impeller on your jet ski doesn’t always need to be replaced unless it’s damaged, and even then, can often be fixed if the damage is minor.
It’s very common for someone to suck up rocks, and it damages the wear ring and impeller. A lot of the time, the impeller can be cleaned up and won’t need to be replaced. If the damage is very bad, then the impeller and wear ring must be replaced.
Over time, cavitation can eat away at the impeller, and a replacement impeller will be needed. You should not only replace the impeller, but figure out what is causing the cavitation or wobble if the wear ring is also damaged for no clear reason.
What Happens When You Suck Something Up?
If it’s small enough, then nothing really happens, and the debris passes through. If it’s big enough, it can stop the impeller and thus shut the engine off.
The good news is that the engineers at Sea-Doo have figured out the solution. You can’t remove all the rocks and sticks from the lakes and oceans, but you can better prepare your watercraft for an event where it sucks something up.
So, what Sea-Doo did and what many other manufacturers do similarly is to use a plastic guard around the impeller which will take the abuse. The idea is that it’s easier and CHEAPER to replace something that is plastic, than the whole metal jet pump housing.
Other manufacturers have wear rings but tend to be metal or not have a wear ring at all. A metal wear ring can be more durable, but more costly to repair. Having no wear ring means the whole jet pump housing needs to be replaced if you do suck something up.
The wear ring has its pros and cons, but what is for sure is that you’ll suck something up eventually, so a wear ring is better to have overall.
How Often Do You Suck Stuff Up?
Sounds scary, doesn’t it? Sucking up rocks and debris into the watercraft and doing damage.
The truth is that it is quite rare to do, unless you’re not being careful. I’ve been playing with watercraft for most of my life, and rarely suck anything up. It happens, much like getting a nail in your car tire.
To avoid sucking up stuff, it’s best to follow some rules…
- Always start the engine in waist deep or deeper water.
- Avoid shallow ground and markers.
- Avoid sucking up ropes.
- Avoid riding after a heavy rainstorm since many sticks break free and hide in the water.
- Avoid debris in the water, like you avoid potholes in the road.
- Always be aware of your surroundings.
- Use a shock tube* when pulling anyone to avoid sucking up the tow-rope.
I’ve seen just about everything get sucked up into the pump of a watercraft. Below is a picture of someone who sucked up a lake map. The blue outer ring is actually the wear ring and didn’t take much damage, but this little bit of paper can stop any watercraft with or without a wear ring. So make sure to avoid sucking stuff up. That little paper map caused the owner running issues, and needed to be fixed.
But Rocks Don’t Float!
It’s shocking to many new jet ski owners when they suck up things like rocks. I’ve gotten a few “but rocks don’t float” arguments from customers before.
Jet skis are a powerful vacuum and will suck up anything in its way. This is why I say you should not start your jet ski in no less than 3 feet of water.
People new to the sport also don’t know about shoal markers and other shallow areas they need to avoid, especially around boat ramps.
Don’t Flip It!!!
If you do suck something up, the golden rule is to never flip the PWC over. NEVER!
I don’t know where the idea came from where everyone flips over a jet ski to get to the intake, but it needs to STOP. It’s dangerous to do that and if done wrong you can do serious damage to the machine.
The best thing to do is to tow it to land and put it on a trailer. Disconnect the battery and then look at the intake for damage. Shine a light from the intake and from the rear to see if you see something stuck or cuts in the wear ring.
Why Don’t They Put A Screen Over The Intake?
I get this often. A screen over the intake would solve many of the problems with sucking rocks and other debris in.
But it doesn’t work, as covered in my detailed post about it here.
Is The Wear Ring Perfect?
No, the wear ring is not perfect, but it does help the whole jet pump housing.
Sometimes something so big can come in and damage the wear ring and the impeller. So, it’s important to be careful when riding and be aware of your surroundings.