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·The leaky carburetor goose cha
The leaky carburetor goose chase – 72 C4
This is one of those situations where my daughter would look up at me and say “da”
After driving the car long enough to warm it up and parking it, I found that gas would seep out of the back (low side) of the carburetors. I had read that DCOEs, especially older ones, were prone to leak through the fuel enrichment circuit, Also that heat form the exhaust would cause the fuel to boil over – again leak through the fuel enrichment circuit.
I was told that the carburetors had been rebuilt when I had purchased the car 4 years ago, so I mistakenly ruled out leaking needle valves. After a fair amount research into the fuel paths in DCOEs and a comment from Jeff that his carburetors were bullet proof – I checked the needle and seat.
By laying the carburetor top “covers” upside down so the floats closed the needle valves and connecting up the fuel lines (and turning on the fuel pumps), I was able to determine that the needle valves were the culprit. $90.00 later with new needle valves, the problem went away. What I also realized, in cars with evaporation cylinders, the valve system tends to cause the fuel tank to take on few positive PSI of fuel pressure, which, if the fuel system is working properly remains in the tank. With leaky needle valves, this will tend to fill the carburetors past the normal level and cause them to leak fuel.
Aaron
The leaky carburetor goose chase – 72 C4
This is one of those situations where my daughter would look up at me and say “da”
After driving the car long enough to warm it up and parking it, I found that gas would seep out of the back (low side) of the carburetors. I had read that DCOEs, especially older ones, were prone to leak through the fuel enrichment circuit, Also that heat form the exhaust would cause the fuel to boil over – again leak through the fuel enrichment circuit.
I was told that the carburetors had been rebuilt when I had purchased the car 4 years ago, so I mistakenly ruled out leaking needle valves. After a fair amount research into the fuel paths in DCOEs and a comment from Jeff that his carburetors were bullet proof – I checked the needle and seat.
By laying the carburetor top “covers” upside down so the floats closed the needle valves and connecting up the fuel lines (and turning on the fuel pumps), I was able to determine that the needle valves were the culprit. $90.00 later with new needle valves, the problem went away. What I also realized, in cars with evaporation cylinders, the valve system tends to cause the fuel tank to take on few positive PSI of fuel pressure, which, if the fuel system is working properly remains in the tank. With leaky needle valves, this will tend to fill the carburetors past the normal level and cause them to leak fuel.
Aaron
