2007 Yamaha Wave Runner ???

[The Right Kind]

Hi, new guy here. I know this question must have been asked before but I can't seem to find it.

I share this Wave Runner with 3 other partners and it really only gets used a few times during the summer months but it seems I'm the only one to maintain it. I've changed the oil several time in the past but I just can't figure out why you can't get all 4.5 quarts of oil out.
I didn't use the ski last year but my brother-in-law did and i have a feeling he road it hard and put it away wet.
After setting for a year, yesterday I picked up the WR and went to change the oil and the oil in it had gone rancid, smells like old fuel.
I think if I don't get all the old out it will contaminate the new oil.

Any suggestions on how to deal with this???

Thanks in advance.

 

[Ernest T]

Re: 2007 Yamaha Wave Runner ???

Your ski uses a dry sump oil system............very different than what you are used to on a car. There is no oil pan for the oil to collect in, rather oil is distributed throughout the engine. When you change the oil, the best you can hope for is to remove about 1/2 the total oil that is in the oil tank. This means if you can get out 2 - 2.5 quarts you are doing well. Be sure to warm the engine up before doing the oil change, and be sure to only check the oil level on this engine with the engine very HOT.........never cold. It is a very common mistake to check the oil level with the engine cold or not completely up to operating temperature and then end up overfilling the oil on this model. Overfilling the oil will ruin the oil filter as excess oil backs into the air box through a breather hose, and will foul the spark plugs making the ski run like crap.

Yamaha has compensated for you not being able to completely remove all the oil, by shortening the oil change cycle. I also recommend changing the oil filter with every oil change.

 

[The Right Kind]

Re: 2007 Yamaha Wave Runner ???

Thanks Ernest T for your detailed explanation.
How often should the oil be changed?

 

[Ernest T]

Re: 2007 Yamaha Wave Runner ???

Yamaha says every 100 hours or at least once per season, and that is what I do. I rarely put more than 50 hours on my ski per season, so mine usually gets changed every 50 hours or so. I also recommend changing the oil filter every year as well, especially if you run in salt water. These filters rust easily, and can actually start to leak if not changed once per season.