k_kleve

Have 97 waveraider 700 with some mods, any left turn from just a slight to hard turn the motor bogs down but flys going straight and on right turns. Went through carb and replaced fuel filter and plugs. What should i look at next?

Ernest T

Usually means a fuel restriction causing leaning. Since you just cleaned the carb, and filters they should be good. You mught try richening the mixture by a very small amount (maybe 1/8 of a turn), to see if that helps. Can also mean the pop off pressure is off, so that would be something else to check.

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2008 Yamaha FX HO Cruiser
2010 Hurricane Sundeck 2100

chomamma2

I've got the same exact condition on a wave venture with a 701 engine. Rebuilt top end, and pump. Runs great straight and right turn. Someone said when going left the pump pushes water up the exhaust causing more power need to push back. I going to rebuild the carbs but not sure if this is really the issue. Let me know what you find out.

Ernest T

Part of the "left" turn bog syndrome has to do with the fact that you are turning against the torque of the impeller. Therefore you are overcoming prop torque which puts considerable more stress on the engine than when making a right turn. The effect of the bog will be more pronounced on an engine with more wear than on a new one.

The other factor involved on some skis has to do with the placement of the carbs. and fuel lines as they relate to the intake. As you make a left turn the fuel flow has to fight against the centrifugal force of the turn, where as a right turn favors fuel flow on some of the older skis.

So, there may be very little at all that you can do to completely eliminate the problem, but you might be able to lessen it.

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2008 Yamaha FX HO Cruiser
2010 Hurricane Sundeck 2100

k_kleve

I richened high side and still no difference. Has 162,170 psi for compression. How do you go about checking pop off?

chomamma2

Just pulled my carbs off and rebuilt them. I couldn't find any pop off pressure for stock carbs, so I set them right at 50 PSI. Ernest, you know what they should be? I'll let you know how it runs when I get it back together.

Ernest T

Yamaha has never stated the stock pop-off pressures used on their skis, so I don't know where a good starting point should be. I've heard that it is fairly high on the newer 2 stroke skis.

Here is a guide for setting it: Shop SBT - Carburator tuning - Pop-off pressure

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2008 Yamaha FX HO Cruiser
2010 Hurricane Sundeck 2100

chomamma2

Rebuilt the carbs. All looked ok though. Took ski out again. Still bad bogg. I opened the high end up a bit at a time and it appears to be getting better, but I am way out of specs on the high end. I check pop off and its 48 on the old spring 50 on the new ones. Seems high but shouldn't be that bad of a difference. I wish I would have checked the main jet size. Wondering if I should try to bounce up a size. Low grunt good, idle good, minor surging in midthrottle.