2007 Ultra250 with a Riva Stage 1 Kit plus a R&D crankcase ventilation kit. I am getting gas in the oil as the ventilation kit fills with apparent blow by. Is there something I can do to prevent this from happening. Local Kawasaki Dealer doesn't know what I'm talking about. They are all about motorcycles and not PWC'S. I changed the oil today and it had a very stong smell of gas. Any ideas

It's a rare occurence that has come up before. I can tell you that it's not the Stage I Kit or crankcase ventilation kit because owners with stock craft have had this happen.

We're not sure what is causing it or how it happens. I can only speculate that it could be a bad injection that drips while the craft is sitting or possibly piston ring blow-by. From what we've heard it takes a while to accumulate so it's hard to track or test for.

You are correct about how much time it takes to accumulate, I did not record the hours, but I would guess about 20, which is also about how long the plugs last as well. Everyone posts their top speed as over 70 mph with a stage 1 kit, the max speed I get on GPS is 66.4.That would be with a 1/4 tank of fuel at 1000 ft. in 90 degree temperatures. There are no codes stored. If an injector was misfiring or leaking, wouldn't it cause a misfire code? There is no engine miss. On a separate note, can the immobilizer be bypassed so there is a direct start when the start button is pushed. In the races that we run, a dead engine start is required. If I don't start immediately, I'm middle of the pack. If it starts on the first crank, I typically win because no one can catch me out of the hole! The 250 has a great hole shot, but not as good on top. A stock boat(Ultra 250) can beat me on the top end right now. Perhaps this fuel in the oil is a contributing factor.

What rpm are you seeing at 66.4? The leak I'm referring to is very subtle. It wouldn't set off a warning. I'm not familiar enough with the 250X's to advise you how to bypass the immobilizer and I haven't heard of anyone else doing it.

search this site i think he bypassed swihttp://www.floridasmarthomes.com/teammoto/?cat=1th

Riva Crew, Sorry I missed the post about the RPM's, the rpm's @66.4 mph is 7640-7660. Is there a need for a different prop at this point, or is there one available that would make a difference

No problem. I do it myself sometimes!

Your rpm is pretty low. You should be running at 7,850 with our Stage I Kit. That would explain the slower speed. You're not turning enough rpm. Are you using the stock prop?

I do have the stock prop, I was not aware anyone made an after market prop yet. Does Riva sell one?

Stock is still the best at that level of modification. We need to find out why you aren't turning the right rpm. Have you inspected the prop for damage?

Riva Crew - I just checked my prop, and the edges are jagged to the touch and there are some visible knicks in the blade. Perhaps that's the source of my RPM loss?

Definitely. You may or may not be able to repair the damage. It's hard to say for sure without seeing the prop. Can you post a few pics of it?

Riva Crew, from a previous post, you had suggested possible damage to the prop as a reason for loss in RPM. To refresh, I have a Riva Stage 1 kit installed and I'm only turning 7460 max RPM. I purchased a new Solas prop from Impros, they suggested a 16/21 pitch for the Ultra 250 with a stage 1 kit. They said that pitch seemed to work the best. We installed the prop and tested. From a standing start, full throttle, the prop slipped badly, cause the engine to hit the RPR limiter for a couple of seconds until the boat caught up. Mid-range seemed improved, but it lugged on top, again only hitting the 7400 RPM mark. Dave at Impros, suggested I return the prop in order to de-tune it to try to get some of the RPM's back. He said he didn't know why the prop was over revving on the bottom, posible cavitation. We did not seal the ride plate or intake grate, but it was the same with the stock prop and there was no slipping. Do you have any thoughts about that? We are going to do a compression test next, to see if perhaps this gas in oil issue has created internal damage. We are looking for the lost RPM's. My top speed with low fuel is 66 mph on smooth water. Prior to the stage 1 kit it was about 62 mph.

I would work with Dave. Impros has been around for a while now. They've established a good reputation for dialing in props.

check the supercharger belt it may need tigteing or changing ,

Jim,
This is more than just a rare incident with the gas in oil problem that you stated with these 07 Ultra 250's. There have been many, I repeat, many cases of peeps having this problem!! Yes, it does eventually cause engine failure. I have been told that Kawi will eventually replace and warranty engine but only for those who are persistant with their complaints and dealer documentation. I had two of the 07 Ultra 250's and I personally had the gas in oil problem with both of them and Kawasaki was of no help. I eventually sold them that same year I bought them. You will need to follow their protocol though in order to eventually have your engine/parts replaced with the newer upgraded parts/rings etc. Make sure your crankcase breather vent is not clogged with silicone...they went crazy on the silicone on the 07's at the factory.
Your lack of speed definitely sounds like it's coming from your jagged prop...an easy place to lose speed and rpm's!