If your engine has trouble running or cuts-out, I have some solutions you can try.
A lot of the time, I find it’s an easy fix, but there are a few things for a few models you need to keep in mind. Let me go over the things you can do below.
Here is a list of reasons why this is happening:
- Gas
- Spark plugs
- Battery
- Clogged fuel injectors/damaged
- Clogged carburetor
- Sucked something up
- Damaged jet pump
- Wrong key or mode
- Blown engine
These are the most common reasons to bog-down or cut off when riding on the water.
Let’s dive deeper into each one.
Why Your Craft Runs Rough
1. Gas
Bad gas is the most common reason I see to bog down or shut off or even sputter while on the water.
This problem tends to happen right at the start of a new riding season because many owners don’t do proper storage procedure.
Gas that will be sitting for months needs to have fuel stabilizer added to it and even then, it’s only good for about 6 to 12 months. This is why I like storing my jetskis near empty during the winter.
How Much Gas?
To fix this depends on how much gas you have.
If the tank is less than half full, I would add premium gas and see if it starts to run better. Though, if the gas is over a year old, then it would be best to get it out safely. Have your local repair shop siphon the old gas for you, as it’s very dangerous.
Add fresh gas to the gas tank and add marine fuel stabilizer (Amazon Link Ad) to the gas just in case there is any water in the fuel lines.
2. Spark Plugs
Up there with bad gas is bad spark plugs, as both will cause running issues for any engine.
The spark plugs are the first thing I replace when it comes to running issues, and you’ll be amazed how often it fixes the problem.
Every Year
You should be replacing your spark plugs every year, it’s that bad of a problem.
And don’t get fancy spark plugs, stick to the ones the manufacturer recommends.
3. Battery
I know, a bad battery may not seem like a reason for it to stutter, shut off, or bog down, but it can.
Most often, it’s not that the battery is bad, but the connections are loose.
A loose battery connection can cause a stutter, shut off, or even bog down. Your engine needs a battery connected at all times to run, or it will shut off or act funny.
Double-check the connection to the battery and if the battery is over 3 to 5 years old, then it’s a good time to replace it.
4. Clogged Fuel Injectors/Damaged
This section is for fuel injected models, basically, you –only- have to press a start button to turn it on. If you have to pull a choke lever or turn a fuel selector, go to the next section.
The fuel injectors are what spray gas into the cylinders, so they can ignite the fuel. These injectors can get clogged or damaged.
The fuel injectors need to be tested to determine if that is the problem. The injectors going bad is not a common thing, so save testing them for last.
Slow Leak
I’ve seen fuel injectors get damaged more than clogged, some will even leak slowly, causing it to not want to start back up after running.
5. Clogged Carburetor
If you have to pull a choke or move a fuel selector lever, then you have a carburetor.
Just about every 2-stroke, besides the direct injection models, used a carburetor, but every 4-stroke is fuel injected. So if you have a fuel injected model, ignore this section.
Carb Clean & Fuel Lines
While fuel injectors going bad is a rare thing, carburetors or the fuel lines going to the carburetor going bad are a lot more common, especially today due to ethanol.
If you have a carbureted engine and tried the gas, battery, and spark plugs, then cleaning the carb and replacing fuel lines should be the next thing you try.
6. Sucked Something Up
Jet pumps are like giant vacuums, they will suck up anything that gets in front of the pump.
Since they are direct drive systems, when the engine is on the impeller is spinning and anything that stops that impeller also stops the engine.
With the machine is not in the water and the engine off, look in your pump to see if anything is stuck in your pump. Check your impeller for any damage and the wear ring too, as they can cause slow take-offs if damaged.
7. Damaged Jet Pump
A damaged jet pump, driveshaft and through-hull seal can cause it to bog down, sputter or even cut off.
This can be a more involved process in fixing and will require taking the jet pump out to check it over.
Make sure the driveshaft is not broken, bent and has its splines intact.
Inspect the jet pump for any holes or missing pieces. To examine the through-hull seal, perform a water leak test on the hull, paying special attention to the area around the drive shaft for any signs of water ingress into the hull.
8. Wrong Key Or Mode
Jet skis, PWCs, Waverunners or whatever brand you want to call them, will have models that have special keys or driving modes.
These modes can be a learning, slow, or ECO type of mode that limits power, makes the unit slow, and to those that don’t know… feel like it’s chugging, wants to cut off, and just don’t feel right.
Make sure you have the right key. When you first put the key on a Sea-Doo, it will say what key you have put on, and it will tell you what modes you’re in.
9. Blown Engine
Last, and hopefully not your problem, is that the engine is blown.
A blown engine has lost its compression or is damaged.
A lot more common on 2-stroke engines, but it can happen to 4-stroke, especially ones that were not taken care of or sunk.
I have a 2007 Sea Doo GTX 155, when I try to go full throttle I get a loud beep and the engine slows down and I get a check engine code PO123. What should I do about this? Do I need to bring it in to the shop or is it something I can fix easily?
That’s a code for the throttle position sensor. Could need a new TPS, a new ECM, or some wiring issue. Best to take it into the shop to see what they can do.