![10 Easy Steps to Maintain a 2-Stroke Jet Ski [Maintenance Guide]](https://www.jetdrift.com/wp-content/uploads/2022/03/2-stroke-jet-ski-maintenance.jpg)
10 Easy Steps to Maintain a 2-Stroke Jet Ski [Maintenance Guide]
Contrary to popular belief, 2-stoke jet skis require as much care as their 4-stroke counterparts. Although they don’t have engine oil to change, a lot of other maintenance tasks need to be done on a 2-stroke ski, including:
- Clean and inspect the ski
- Clean and rebuild the carbs
- Check the spark plugs
- Clean and inspect the valves
- Inspect the fuel system
- Check the oil injection and replace oil lines (if present)
- Maintain the pump and the driveline
- Greasing the moving parts
- Take care of the battery
- Winterizing (at the end of the season)
We at JetDrift have compiled all you need to do into this step-by-step guide!
How to Service a 2-Stroke Jet Ski
Besides the regular after-ride care, each jet ski requires yearly maintenance, and 2-stroke skis are no exception.Best practice is to perform these maintenance tasks at the end of the season, at the same time as winterization.
Let’s get down to the nitty-gritty and see how to service a 2-stroke jet ski!
Disclaimer: This post is for general informational purposes only. Read your ski’s service manual for model-specific instructions before you do any maintenance on your jet ski.
1. Clean and Check for Damage
As a first step, thoroughly clean the ski. Besides the hull and deck, don’t forget to clean the seat, storage compartment, and engine bay.
While doing this, check for damage and oil leaks. Oil drops in the bilge are always a sign that the engine and oil system need a closer look.
2. Clean or Rebuild the Carbs
If you have a carbureted jet ski, you will also have to periodically clean or rebuild the carburetors.How often should you clean the carburetors on your jet ski?
While some rigorous owners clean their carbs every year, others only do this every 2-3 years. Since it’s cheap insurance, you may want to clean and check them annually, but at least every two years.
A hidden advantage of removing the carbs is that it allows you to do a compression test on the engine. A leak test is a good way to uncover hidden bugs in the engine.
Beyond cleaning, jet ski carbs also have to be occasionally rebuilt.
How often should you rebuild the carburetors on your jet ski?General wisdom says that if they aren’t broken, don’t fix them. If you maintain and clean your carbs regularly, they can operate for many years without any issues.
When it comes to rebuilding a jet ski carburetor, you can choose from various rebuild kits.
Simple kits only contain the rubber parts like gaskets, diaphragms, O-rings, and the fuel filter. These parts are prone to aging and breaking over time, but they are easy and cheap to replace.
In contrast, full rebuild kits come with everything you need for a complete rebuild.
These packages typically include airscrews, valves, jets, springs, and float arms. However, don’t forget to double-check the kit list, as certain parts may be sold separately.
Since these complete kits are not cheap, you should only fully rebuild your carbs if they show excessive wear.
If your ski features fuel injection instead of carbs, you need to realize that this system also requires periodic inspections and maintenance.
Unfortunately, fuel-injected jet ski engines are harder to maintain and fix than their carbed counterparts.
3. Check the Spark Plugs
You should also check the spark plugs on your ski and replace them if needed.
How often do you need to change the spark plugs on a jet ski?
As a rule of thumb, you should replace the spark plugs in your jet ski every couple of years. Best practice is to check and replace the plugs in your ski as indicated in your owner’s manual.
But if you are a hardcore rider who puts a lot of hours on the engine every year, you may want to consider replacing them every year.
4. Clean and Inspect the Valves
Valves on a 2-stroke jet ski? Yes!
It’s a lesser-known fact that you can also find valves in most 2-stroke jet ski engines.
On the intake side, you can find reed valves, which are intended to restrict the flow of fuel to one direction. Reed valves are commonly used on vintage 2-stroke Yamaha and Kawasaki engines.
In contrast, most 2-stroke Sea-Doos feature a rotary valve, as the only Sea-Doo engine with reed valves was the Rotax 951 twin.
What’s more, high-performance 2-stroke jet skis are also equipped with power exhaust valves, which ensure higher performance and more bottom-end power.
On Sea-Doos, the power valves are called R.A.V.E. (Rotax Adjustable Variable Exhaust), while on 2-stroke WaveRunners these valves are labeled Y.P.V.S. (Yamaha Power Valve System.)
These valves also have to be inspected and cleaned annually.
5. Inspect the Fuel System
You should also inspect the fuel system, including the fuel lines, pump, and tank.
Check for cracks and leaks and replace the hoses if needed. The fuel filter also has to be replaced annually.
Ensure that the fuel pump works properly, as it can produce various malfunctions over time.
6. Check the Oil Injection and Replace Oil Lines
Do 2-stroke jet skis use engine oil?
Due to its design, 2-stroke jet skis burn the oil along with the gas. Therefore, a 2-stroke jet ski engine doesn’t hold any engine oil. Instead, they use special 2-stroke oil stored in a separate oil reservoir. While the engine is running, it’s sucking the oil from this reservoir and automatically mixing it with the gas.
Do 2-stroke jet skis need oil changes?
For the reasons above, the engine of 2-stroke jet skis doesn’t require oil changes. However, the pump oil of these machines has to be replaced annually.
One of the most important systems of a 2-stroke jet ski is its oil injection. Only a little malfunction in this system can leave the engine without lubrication, resulting in an engine seizure.
Check the oil reservoir, pump, and oil lines carefully for damage. Best practice is to replace the oil lines every 2-3 years for safety reasons. It’s a cheap investment that can save you from an engine rebuild!
After the replacement, don’t forget to prime the system to ensure that it works properly.
If the oil injection system is bypassed on your ski, you don’t have to deal with this maintenance task.
However, if you have a 2-stroke Sea-Doo that runs on premix, don’t forget that 2-stroke oil still lubricates the rotary shaft bearing and gear. So you need to check the hose connecting the engine and oil reservoir.
Also, refill the reservoir with the appropriate 2-stroke oil.
7. Maintain the Pump and the Driveline
Like the engine, the pump of a 2-stroke jet ski also requires an annual inspection as per the service manual.
Unlike the engine, the pump of a 2-stroke jet ski holds oil that must be changed at the end of the season.
The more advanced 2-stroke skis were also manufactured with a manual reverse system. Compared to the modern iBR and RiDE systems, these vintage reverse units feature a fairly simple design.
Despite this, they also deserve a close look when doing yearly maintenance.
The driveline of these skis is often overlooked, but a broken driveshaft sealing can cause the machine to sink!
While WaveRunners and Kawasaki jet skis utilize a more advanced shaft housing and coupler, Sea-Doos come with the notorious carbon ring seal. The latter is prone to leaking due to uneven wear.
To keep your ski afloat, it’s recommended that you check this sealing on your ski, and not just once a year! You should check the carbon seal/shaft housing for leaks after every ride as part of the after-ride care.
8. Greasing the Moving Parts
You also should lubricate the moving parts and grease all bearing fittings and seals.
You can find a detailed list of these parts and the recommended lubricant in your ski’s service manual.
9. Take Care of the Battery
The battery of 2-stroke jet skis also has to be inspected and removed for the winter months.
Best practice is to store it in a dry cool place and hook it up to a battery tender.
10. Winterizing – How Do You Winterize a 2-Stroke Jet Ski?
Contrary to popular belief, a 2-stroke jet ski has to be winterized.
How do you winterize a 2-stroke ski?
The winterization process of a 2-stroke ski is almost the same as a 4-stroke model. In a nutshell, the key steps of the process are as follows:
- Empty the storage compartments
- Clean and inspect the ski
- Top off the tank, add fuel stabilizer and run the engine for 2 minutes
- Do the scheduled annual maintenance
- Drain the water from the systems and the bilge
- Flush the cooling system and exhaust with antifreeze
- Spray fogging oil on the carbs and plugs
- Remove the battery
- Cover it up
- Store in a secure place
Any water accidentally remaining in the systems can freeze, causing severe damage.
Takeaways
Just like their 4-stroke brothers, 2-stroke jet skis also require periodic maintenance.To keep your ski in good shape, you should maintain and winterize it according to your owner’s manual. Remember that the exact process may vary from one model to the next.
Fuel-injected and high-performance carbed jet skis require more care and attention due to their more complex engine and features.
Finally, don’t forget that each 2-stroke jet ski has to be winterized before the off-season. It’s always a great idea to do the annual maintenance and winterizing at the same time.
