Another Carburetor Project.

Hi Scotch, "No" still bench testing the carbs and still over fueling. With tube gauges installed a suspended fuel tank. When left for 10 minuets all levels seem to get high, towards the top of the fuel bowls. Then one of them will overflow !!!  almost if the fuel is trying to find the weakest link or the path of least resistance. Then if i move the position of the carbs it will happen on one of the other carbs.  This bike is testing me like no other, even had members of the local bike club round here, checked everything on the carbs. Still don't know what it could be. I have owned 100's of bikes over the years not one had a un-fixable problem. This is going into the realms of the supernatural. Think i will call her Christen    No one can sort out this problem out ! 

A) Open tank gas cap or gas can, be sure it's fully vented and NOT pressurizing the system
Weigh the floats.. I have an OEM set somewhere, perhaps Scotch can tell you what his brass floats weigh. Too heavy = minimum shutoff capacity.
C) Check carb fuel needle and seats, and if they look good replace them anyway!
D) Manually manipulate the float  using your fingers. Do each of the 3 stop flow? All flow? If so,
E) Find about 10 feet of fuel line, connect one end to carbs inlet, other end open. Fill with line with gas. Allow all float bowls to fill. Use a big diameter syringe to 'pressurize' the fuel line and fuel rail. If just a wee bit of syringe pressure allows flow, you'll know to look more carefully at items listed above.

Forgot to add, is the fuel system clean, clean, clean? I chased a problem on a HD Evo engine, over fueling the bowls, turned out to be various chunks of rubber fuel hose lodging and holding the fuel needle partially open.

Also, do the floats move freely, no binding, at various carb angles?

It's not that complicated of a system, and I too tend to way 'overthink' things..
Hope I've not offended you with my trying to help comments... I'm just a back yard hack that understands frustration when problems don't get fixed!

YES to all, done everything here ! carbs clean. These are bench tested and not connected to the main tank. All new float valves. New floats.
Thanks for the response.

z13phil wrote:

YES to all, done everything here ! carbs clean. These are bench tested and not connected to the main tank. All new float valves. New floats.
Thanks for the response.

 

Performed?
D) Manually manipulate the float  using your fingers. Do each of the 3 stop flow? All flow? If so,
E) Find about 10 feet of fuel line, connect one end to carbs inlet, other end open. Fill with line with gas. Allow all float bowls to fill. Use a big diameter syringe to 'pressurize' the fuel line and fuel rail. If just a wee bit of syringe pressure allows flow, you'll know to look more carefully at items listed above.

In Grams

 

Before or after the ink?