2000 Mercury 45 jet issue?

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I have a 2000 Mercury 45 jet, it is leaking gas out the carbs when running. I have took the carbs apart and cleaned didn't notice any issues. Also on the top end running wide open it has a small stutter. I believe it's a fuel issue but not sure where to start? The marina wants 95 dollars to diagnose the problem and 95 dollars an hour after. Would I have a float stuck? I can probably get a video on a day or two of the motor running. Also doesn't seem to have full RPMs.
 
Did you adjust the tabs on the floats to the correct position to stop the fuel at the needle valve? Did you replace the needle valves, it's seats and floats? What is the condition of the needle valve and it's seat?

Some floats have two tabs, one to limit how far it drops to allow the bowl to fill and of course the one to shut off flow at the needle when the fuel is at the correct level.
 
no i just cleaned them and didnt see anything out of the ordinary. But i am not really a marine mechanic. I hate to take it and pay all that money but i am running out of options. It had a rubber needle under the float it looked good.
 
With the float bowl off turn the carb body upside down. Pretty sure the float level should be parallel to the bottom of the carb body like this.
setfloat.jpg
If not bend the little tab on the float that controls the needle valve till its level.
Check the sealing surface in the orifice where the rubber tip of the needle valve seats. Is it corroded?
 
I pulled the carbs off today and they were full of small black crud. I did notice the other day in the gas tank the same foreign material so I dumped it all out best I could. I plan on taking the boat out soon so hopefully it helped! Although last time I cleaned then it helped but it still surged once in a while.
 
Walkerdogman85 said:
I pulled the carbs off today and they were full of small black crud. I did notice the other day in the gas tank the same foreign material so I dumped it all out best I could. I plan on taking the boat out soon so hopefully it helped! Although last time I cleaned then it helped but it still surged once in a while.
Hopefully your lines aren't deteriorating, if so that could be the source of that "crud". If so you will need to replace them, that crud under the needle valves will not let them seal off causing the situation you are experiencing. If your floats are set correct and you don't experience anymore of the crud I would change the needle and seats, they aren't expensive.
 
I plan on hopefully changing all my lines as this is twice now in just a few months that I have had to clean the carbs. I just wonder why at wot the motor seems to have a stutter? Also is there a way to adjust RPMs? I think it needs more RPMs. It starts perfect and life's fine. I can pull back to 3/4 throttle and it won't stutter
 
Walkerdogman85 said:
I plan on hopefully changing all my lines as this is twice now in just a few months that I have had to clean the carbs. I just wonder why at wot the motor seems to have a stutter? Also is there a way to adjust RPMs? I think it needs more RPMs. It starts perfect and life's fine. I can pull back to 3/4 throttle and it won't stutter
I would get it running correctly first then get a tach on it to see exactly how many RPMs it is turning prior to adjusting on it. It should have been set correctly from the factory and shouldn't be off much unless someone has messed with it.
 
I did buy it used. It just doesn't seem to have enough compared to some other guys 2 strokes on the river
 
How do your plugs look? If their white or light tan you are running lean. Bad news for a 2-Stroke.
 
If it is sputtering, like you say the plugs should be wet/black. The first thing I would do would be get the carbs/fuel issue corrected then move on to the other issues. Like was mentioned check the plugs and see exactly what RPMs you are turning.
 
I get some sputtering at 2/3 to WOT sometimes if I don't pump up the fuel ball until it's firm. When I do get the sputtering, it goes away after 4-5 minutes so my issue is probably different. But it makes me think there is air in the fuel line so it's worth checking.
 
I pump mine until hard, but while operating I have tried pumping and it doesn't change. It only does it once in a while and after the carbs are clean it won't do it for a while
 
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