# Yamaha OX66 250 VST cleaning



## bonedaddy (Sep 8, 2008)

I was out on Sunday and running about 4800 RPM everything was fine and all of the sudden the boat just lost power. It didn't shut off, I gave it gas and took off again (this hppened 3 times total). I have read that my motor has a Vapor Seperator Tank that could cause the motor to loose fuel pressure if it is dirty. Does anyone have any suggestions or know how hard it is to clean this tank?


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## DOUBLE "D" & LV (Oct 2, 2007)

There is a drain on the side of the VST. If you check it for water and none comes out, you may have to open the VST. If you do, you need to get a new o-ring for the cap and I would recommend getting a new filter inside of the VST. HOWEVER, I WOULD HIGHLY RECOMMEND MAKING SURE IT IS THAT BEFORE OPENNING IT UP. I have found that there are a lot of other issues to cause what you described. If your primer bulb goes flat, you have a restriction before the bulb; if the primer bulb seems to leek down, you could have a ruptured diaphram on one of your fuel pumps; there is a check valve on the engine that can stick and cause the engine to die; a loose fuel line connection can cause it. I only say this because the VST has your electric fuel pump in it and the VST is full of fuel. If you are not careful, you may get into more that you want. The VST is not hard to do if you pay attention and put it back without damaging anything. Call me if you need more info.


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## Sequoiha (Sep 28, 2007)

All good info David,,,,, I can take care of it for you as well....:usaflag


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## Bowed Up (Oct 4, 2007)

O2 sensor port clogged?


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## Wooly Bully (Oct 19, 2007)

could also be 1 0f 3 fuel pumps.. if one of the fuel pumps has a tear in the diaphram, it will cause the same thing.. had to replace all of mine and it cost about 130 bucks.. hope this helps


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## bonedaddy (Sep 8, 2008)

Thanks to everyone for replying, I am going to have it looked at next week!


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