Hey guys,
I thought the fuel return valve was working fine after doing few tests on it(RB30 carby model), but apparently it isn't.
RB30 fuel return valve is "piggy backed" via engine RPM sensor unit.
Basically, when engine rpm hits around 1500 or more the Fuel Return Valve closes & effectively allow less fuel to return
back to the tank, which in turn increases the fuel pressure when engine's under load or accelerator pedal is pressed, allowing more fuel to the fuel bowl(carby).
My carby's been having issues with rich mixture(carbon soot build up on spark plugs) and hesitation when mixture is leaned to address the excessively rich mixture issue.
I can't say for sure, but it appears blocking the fuel return line and stopping fuel from getting to the fuel return valve appears to have fixed the problem.
Does this mean I've been having a fuel pressure issue, rather than a carby issue(rich mixture)??!!
Blocking fuel return line has improved the carby float level as well. Before it was very low.
Do I have a malfunctioning RPM counter unit(I think it's under the dashboard in driver's side) or a malfunctioning
Fuel Return Valve?! Or do I have a week fuel pump(in tank stock pump was used)
How does that having more fuel pressure improve excessively rich mixture issue?
Doesn't low fue bowl float level mean leaner mixture, rather than richer mixture?
Thanx