Superjet not accelerating after warming up

[Galaitoto]

1990 760 dual carbed headache maker. I'm still learning about this thing, so my description will be kind of vague. I took it out to perris lake in so cal for a test run after having it tuned up. The mechanic said the carbs are still in good shape, and jetted correctly for my elevation. It fired right up, and acelerated perfectly on Lap #1. I crashed on lap #2 but did not tip it over, I just fell off the side. It fired right back up, but it would not accelerate. I had to feather the throttle in the mid range area for 2-5 minutes before it would come back to life. It seemed to get worse as the day went on. Any clues what to check for? As always, thanks for the help from all of you guys and gals.

 

[SVTPete83]

Water in your filters. Do you use outerwears? Stock filter setup or AM? My sn does the same thing. Usually doesn't take 5 mins to dry em out but it will take a min.

 

[Galaitoto]

Here's what the filters look like

 

[SVTPete83]

Looks and sound to me like they are getting wet.

 

[Galaitoto]

Interesting, thanks. So what should I do?

 

[SVTPete83]

Do you have the vent tubes off the bottom of the hood on? They usually will keep the filters from getting hit with too much water. Outerwears will help too

 

[Galaitoto]

I'm not sure, I'll check. I did not notice any holes, other than the vents in the top of the hood. But those vents are open with nothing under them to deflect the water. I'm not sure if that's what you mean or not? And I'll get those outerwears

 

[SVTPete83]

This is the bottom of my sxr hood. Those black tubes are vent tubes. They allow air to fill the engine compartment through holes in the top of the hood. As the ski tips or your crash, water gets in the hood vents. The tubes are there to direct the water towards the bottom of the ski, away from your engine air filters.

 

[Galaitoto]

Thanks for the picture, I went out and checked, indeed the vent tubes are missing. I had no idea that just riding without falling would allow enough water inside to mess it up.

 

[SVTPete83]

It doesn't take much water to get those filters wet and make the ski run like poop till they dry out. Glad I could help out!

 

[Galaitoto]

You were beyond helpful! Thanks so much. Last question, are they just basic rubber hose? Can I buy from Home Depot? Also, how long are they?

 

[SVTPete83]

I know on a square nose there is a long and short one. Not sure on exact length. There is probably a good alternative to the stock ones. Maybe someone can chime in.

 

[Galaitoto]

Ok thanks, I'll research it. Unless someone here knows. Thanks again for your help !

 

[SXIPro]

I never understood the design or placement of the SN hood 'vents'. Just leaving your ski out on a rainy day could fill your engine bay with water.

 

[Galaitoto]

Seriously, and I had no idea that water could get down the carbs so easily. It makes sense to me though now that I think about it. I knew that it couldn't be a carb tuning issue because it was not giving me the usual symptoms of being to rich or lean. It was something else, and I think you guys have nailed it. Thanks a million, I can't wait to give it a try soon.

 

[Galaitoto]

Is this what I need?

 

[SVTPete83]

Yep. Frickin blowsion. Millions of dollars for everything!

 

[Galaitoto]

I was getting the impression that they are a very pricey company. Now that I know what I'm looking for, I can shop around. Thanks again!

 

[Vortex]

Another fix is to install frogskinz, they allow air but keep most of the water out due to surface tension, I've used them for years after I cut the vent tubes off. Never had an issue but I'm also running outerwears.

If you get them use a little superglue to add strength to the adhesive backing.

 

[Galaitoto]

Thanks for that. I just ordered the tubes from jetmaniac. I will look into your suggestion as well, thanks !