mercury 650 carb issues

Jhopper

Cadet
Joined
Jan 25, 2016
Messages
20
Well I dug in to remove and rebuild my own carbs. I'm very mechanically inclined but I know absolutely nothing about outboard engines. I managed to get everything removed to access the carbs for removal. I unbolted and removed the upper carb. Only to realize I broke the piece that connects the throttle to the lower carb. Yay me. 😒 so if anyone knows where I can get one of these please let me know. Also, my carb actually looks clean. Not gummed up like expected. Yet on the engine the carbs flood and run like crap. So now I'm here seeking advice and to know what carb kit to order and what to remove and not remove to clean\ rebuild. Thanks in advance guys.
 

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,544
Adjacent to the hinge for the float is the fuel inlet needle valve, operated by movement of the float. Unpin the float and remove the needle(s) and have a look at the conical tip. It has to be perfectly conical to work properly...no rings or other distortions. Take the float and set it in a pan of water. It should float like a cork; if not replace it. Crud in the venturi tube (tube that connects the carb bowl to the venturi opening....where the air comes in and the fuel sucked out of this tube mixes with it) can mess up performance. A piece of wire poked in every hole you see, then aerosol carb spray (Berryman's Chem Tool aerosol) and then a good blowing out with 100 psig compressed air to round it out. Carb kits come with a little card used to set the float but basically if you turn the carb upside down with the bowl removed the float should "gravity" rest parallel to the casting flange of the rest of the carb as it holds slight pressure on the needle valve.

Go on the www and get your linkage. Lots of sellers. Don't think Iboats handles those kinds of parts.
 

Jhopper

Cadet
Joined
Jan 25, 2016
Messages
20
Thanks for the reply texasmark. Do you know what to call that piece between the carbs that broke? That way I know what to search for
 

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,544
Thanks for the reply texasmark. Do you know what to call that piece between the carbs that broke? That way I know what to search for

Just carb linkage as far as I know. You should get a parts breakdown where the whole link and sink linkages (carbs, timing, and connection to the internal throttle lever all in one picture with numbers that are traced to a parts list with OEM numbers and pricing.
 
Top