Wear Ring Issues
In addition to understanding how a Jet Ski propulsion systems works, you need to have a mechanical understanding of other components of your Jet Ski. Repairs and modifications are not incredibly challenging to make, but if you lack the right knowledge, they can seem impossible. You need to be aware of a Jet Ski’s wear ring, its function, and how to tell when yours is getting old. The wear ring, as its name indicates, is a ring that will wear out over time that is fastened around the impeller. Unfortunately, as with all other mechanical parts, the wear ring breaks down over time and you will likely need to replace one if you own a Jet Ski for any substantial amount of time. Every minute of fun spent accelerating your Jet Ski will decrease the useful life of the wear ring. You must understand that the wear ring, combined with the impeller, is crucial to the process of water jet propulsion.
Impellers vs Propellers
Understanding the function of the wear ring is dependent on understanding the impeller. The impeller on a Jet Ski is very similar to the propeller on an airplane, but it creates propulsion using water instead of air. The impeller helps to push water behind the Jet Ski to facilitate motion, but an old wear ring will inhibit the impeller’s ability to do so.
Achieving Propulsion
The wear ring is designed to fit around the impeller with a small gap (approximately .005”) between the edge of the impeller blades and the edge of the pump housing. Over time, each impeller rotation eats away a little bit more of the wear ring due to the abrasive nature of flowing water between the impeller blade tips and the inside diameter of the pump housing. In addition to that, small particles of debris in the water are frequently sucked through the pump. Debris further decreases the useful life of the wear ring by causing ruts and gouges. As the wear ring slowly breaks down, the space between the impeller and the wear ring will grow.
When to Replace a Wear Ring
There are a few common signs that will help you identify an old wear ring. If you notice any of the following common symptoms, it is more than likely time to inspect or replace your wear ring:
- Your Jet Ski won’t accelerate as quickly and tops out at a lower speed than before, even though your engine’s RPM operating range seems fine. This will make your Jet Ski feel as though it is sluggish and has lost some power.
- You need to rev the engine to higher RPMs to get the same amount of acceleration and thrust.
- You notice abrasions, grooves, and excessive wear-and-tear when you visually inspect your wear ring. When the gap between the impeller blades and the wear ring increases (beyond .005”) due to erosion, you will lose a lot of energy because it passes around the impeller.
Conversely, a new wear ring will give you optimal speed and acceleration by efficiently pushing water behind your Jet Ski.
