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4 Best Ways to Test the Oil Injection System on a Jet Ski [Video]

4 Best Ways to Test the Oil Injection System on a Jet Ski [Video]

After replacing the oil lines on your jet ski or servicing its oil injection system, it makes sense to check whether the oil pump is working properly.

Without further ado, the four best ways to test the oil injection system on a jet ski are as follows:

  1. Manual test
  2. Pressure test
  3. Drill test
  4. Visual check
If you want to find out more about these methods, you’ve come to the right place.

We at JetDrift have compiled all you need to know into this post!

4 Best Ways to Test the Oil Injection System on a Jet Ski

Before you perform any tests or service your ski, it’s highly recommended that you read the service manual. If you are not comfortable doing this repair, you should take it to a professional.

Keep in mind that a little malfunction in the oil injection system leaves your engine without lubrication, which results in an engine seizure.

1. Manual Test (Best Practice)

The best way to make sure that the oil injection works is known as “manual testing.” How is this done?

As the first step, you have to spray some oil into the carbs for safety reasons. This little bit of oil will ensure that the engine gets some lubrication even if the oil pump isn’t working.

Locate the oil pump lever and pull it wide open. Then fire up the engine and let it run for about 30 seconds at idle speed. With this trick, you can force some extra oil into the carbs.

If you apply some throttle, the excessive amount of oil will generate massive smoke. If your ski smokes like a factory’s chimney, you can be sure that the oil injection system is working!

2. Pressure Test

Manufacturers also recommend doing a pressure test on the oil injection system after its components have been disconnected or replaced.

The exact process may vary from one model to the next, so don’t forget to check your ski’s service manual before doing this test.

Generally speaking, on most skis, you have to fill up the reservoir and install hose pinchers on all oil lines.

You will also need a “leak tester kit,” which typically contains a small pump with a gauge that has to be attached to the oil reservoir vent line.

To test the system, you have to pressurize it at a specific pressure. If the pressure is not maintained, you have to check the hoses and connections for leaks.

Keep in mind that even if the system is completely sealed, it won’t automatically indicate that the oil pump is working properly!

3. Drill Test

How do you test the oil pump on a jet ski?

If you want to ensure that the oil pump works on your jet ski, you should remove and test it with a drill. Unfortunately, this test is quite messy and requires a lot of effort as you have to pull the oil pump out of the ski.

As the first step, disconnect the oil lines and remove the oil pump from the engine.

Put the pump in a bench vise and tighten it securely. Attach a short rubber hose to the inlet nipple and fill it up with engine oil. Also, loosen the bleeder screw as the pump may not work if air is blocking the system.

Attach an electric drill to the pump shaft and smoothly spin it. If the pump works properly, you should see oil dripping from the outlet nipples.

Here’s a great step-by-step tutorial on how to test the oil pump on a jet ski:

4. Visual Check

Last but not least, don’t forget that you can also visually check the system if the oil injection points in your intake manifolds are visible. How can you do this?

First, spray some oil into the carbs or the cylinders again to make sure that the engine gets some lubrication.

Shut off the fuel line, remove the spark plugs, hold the throttle (or the lever of the oil pump) wide open, and crank the engine. (The absence of spark plugs allows the engine to run much faster.)

Check the intake manifolds; if the oil pump works, engine oil should be dripping from the inlets.

Conclusion – How do You Know if Your Jet Ski’s Oil Injection is Working?

As you can see, there are many ways to make sure that the oil injection system is working on your jet ski. The easiest way is arguably a “visual check,” but it’s recommended that you not rely solely on this method for safety reasons.

Instead, you should “manually test” the pump, which means running the engine at idle while keeping the oil pump lever wide open. If the system is working correctly, the ski will produce massive smoke when you hit the throttle.

Another common method for testing the oil pump is the drill test.

This inspection requires you to remove the pump from the engine, secure it in a bench vise, feed it with some oil, and gently spin it with an electric drill.

No matter how you test the pump, make sure to spray some oil into the carbs before starting. If you want to be cautious, you may want to drain the fuel tank and fill it up with 40:1 premix. Even if something goes wrong, the mixture will save you from an engine seizure.