It’s very important to understand that the Rotax engine, due to having dual oil sumps, has a special procedure to properly check the oil level. If this special procedure is not followed, almost always the result is a low reading, resulting in too much oil added to the engine.
In order to properly check your oil levels to perfect, the engine must first be at operating temperature, which usually means in the water. With the boat sitting level in the water, you should let the engine idle for approximately 30 seconds, shut the engine off, then measure your oil levels about 30 seconds later.
If you do not do this, and try to check it cold in your driveway, or any other way, it’s likely it will read low, and you will add too much oil trying to top it off! The engines are negatively sensitive to having too much oil, so it is highly recommended you check the oil properly, and keep it just under the full mark.
You can find more details instructions in this guide, but be aware, the manual indicates this can be done on the trailer, but I’ve rarely gotten good results this way. Having the boat warmed up, in the water, will give you a perfect result.
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