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I have two 07 Yamaha VX Cursers, I have done an oil change every year. Every year after the winter, I look at the oil levels and the oil is not to be seen in the reservoir. Previous years I vacuumed the oil out and added new oil but this year I decided to just top them off.
Bad Idea.
I put the oil in to the full lines, ran them for about 5 min and discovered that they where burning oil ( smoke out the back) I turned them off and saw that oil was dripping from the air filter. The oil had increased in volume and was overflowing into the heads and air intake trough the breather tubes. Well i thought the worst. They where not winterized properly and the water was shutting into the oil. I vacuumed the oil out and let it sit but no water. replaced the oil back to the full level and tried it again.
It looks like i sucked out the same amount of oil that I put in when I saw that it was low.
Does any one know where the oil was hiding? Is there something that I could look for.
The Yamaha VX and most of the FX models use a Dry Sump oil system that puts the oil in essentially 2 separate compartments. This is very different than what you find in your car, lawn mower, etc., where the oil resides in the crankcase and oil pan. The Dry Sump system allows them to build a smaller more powerful engine that can be tucked away inside a waverunner, but it also requires you to take additional steps when checking or changing the oil. The Dry Sump system lets the bulk of the oil sit in a reservoir and eliminates the need for an oil pan so the engine can sit lower in the ski (improves the center of gravity). It also eliminates problems with the oil sloshing around in the engine during banked turns, etc. There are many advantages to this system, but it also requires different handling and maintenance procedures.

Revisit your owners manual, and you will find a section that tells you that the engine must be warm to get an accurate oil level reading. They usually tell you to check the oil after you have been riding long enough to sufficiently warm the engine or to warm it on a hose for at least 6-10 minutes first before checking the oil level. It is necessary for the engine to run in order to distribute the oil through the engine and into the oil reservoir where the dip stick is at. If you check the engine cold it will ALWAYS give you a low reading, because the oil has had time to drain out of the reservoir and down into the engine. The end result is overfilling the oil chamber as you did. Then when the engine is warm oil overflows onto the air filter resulting in a $100 boo boo to replace the saturated air filter (which I assume you did, since it doesn't work saturated with oil). You can also make a mess and foul the plugs this way.

Don't feel bad, this is probably the most common mistake made with this type of engine. Most folks don't repeat the mistake after having to buy a new air filter, if that is the worst you have done.

You should always warm the engine up before changing the oil also. Otherwise, you will not get very much oil out, and you will leave all the particulates at the bottom of the crankcase and not suspended in the warm oil. You may need to extract some of the oil, warm up the engine and check it again. I'd try to shoot for about 1/2 way between the full and low marks on the dipstick.

There is actually a drain plug on the bottom of the engine that could be used to remove all the oil, but it is very inaccessible, and I think you would end up making a really big mess trying to drain it that way.
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