I have been troubleshooting an annoying miss or stumble since this summer. In a previous thread I listed the countless items I have checked or replaced in an attempt to solve the problem.
Now I think I may have discovered the culprit and so here is my question- can a NH Holley that has the float set to high or the needle and seat not closing properly causing the bowl to over fill produce a stumble because fuel has gotten into the other passages?
Your thoughts would be appreciated.
Fuel too high in the bowl would doubtless cause an over rich condition.
I disagree, the fuel going to the engine is regulated by the needle vavle. If the float is set to hight it will cause the fuel to run. out the over flow
If it's in the carburetor I'd suspect fuel starvation from a bit of debris stuck in a passage, or a float valve sticking shut.
If the float gap is set too small (less than 15/64" to 1/4") the fuel level will rise too high before the tab can close the needle valve resulting in an overflow. If the gap is set too wide (greater than 15/64) the tab will push the needle closed too soon and you will be perpetually starved for fuel, even with a full tank. Gap is measured from the machined flange to the top of the flat portion of the float with a feller gauge you can make yourself. Measurement is taken on the side opposite the hinge with the carb upside down so the float is closed. Jim Patrick
feeler gauge, not feller...
Good, Jim. Too often we recommend what to do without saying how it's done.