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we have a 150hp mercuiser and when we were at the gorge last week something happened with the motor it is only giving 2000-2200 rpms when under way and if you give it more gas the motor will start to stall out and you have to keep it at about 1/2 throttle any ideas on what to try when it sits at idle the motor runs fine and the rpms will go up with the more gas you give it but when you put it in gear and start to go rpms go up and then when you hit about 1/2 way on the throttle it stays at 2000rpms and if you give it more gas the motor will start to stall out any [url "http://imhooked.com/cgi-bin/forumsyabb/YaBB.pl?num=1340850289#"]help[/url] would be great weve put a can of seafoam through it and are looking at giving it a tune up so any help on what to check would be great thanks
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There are a bunch of things it could be but it sounds like a carb issue. Is it a 4 cyl inboard? How much of the tank of gas did you use, once you put the Seafoam in it? Was water coming out of the pee hole? When was the last time you checked the fluid in the foot?
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its a 6cly inboard outboard so no pee hole we used about 1/2 the tank of gas the lower unit was rebuilt about 1 month ago so all the fluids are good to go im thinking well need do rebuild both carbs
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There is a way to check which carb is running bad. You just need to take the boat out on the water, take the cover off the carbs, where you can get enough room to cover each carb one at a time. Get up to the speed where it starts running bad, then put your hand over each carb one at a time. The carb that you cover that makes the engine die of just about die, will be your good carb. Of course this will not matter if your planning on over hauling both carbs but it could be something as simple as a pluged filter going to that carb. Some had a filter in each carbs, at the inlet fitting. Hope that helps.
WH2
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It sounds to me like a fuel delivery problem. Check your fuel filter and fuel pump.
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We had the same problem a few years ago. It ended up being a throttle cable problem actually. There is a mechanism on the engine attached to the cable, when its not in gear the motor ran fine, but when engaged something on that mechanism would not work due to wear. Lees marine did the repair , and it functioned perfectly after that, Cost me 600 though. ouch!!
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