Starting Problems
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Joined: Jun 2004
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From: tierra verde fl
Starting Problems
My 1962, 327-300 is very hard to start after sitting a while. In checking the Carburetor I notice the Carburetor dry, so I assume the gas flows back to the tank. So it requires many attempts of starting until gas gets to the carburetor.Has any one installed a check valve to prevet flow back of gas to the tank? If so has it helped? Outside installing a electronic fuel pump are there any other solutions?
Team Owner
Joined: Feb 2003
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From: Sitting in his Nowhere land Hanover Pa
2024 C2 of the Year Finalist - Unmodified
2015 C2 of Year Finalist
There is a check valve in the fuel pump. The gas is evaporating. It's best to either let it crank until fuel is pumped back up or get a turkey baster and fill the bowl up with gas though the vent
Race Director
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From: San Antonio, TX/Mahopac, NY
2024 Corvette of the Year Finalist - Modified
2024 Corvette of the Year Finalist - Unmodified
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I use the turkey baster, but beware not all of them hold the gas until you squeeze the bulb. The first one I stole from the wife and as fast as I sucked up the gas was as fast as it dribbled out the end. I got a glass one on Amazon and it works well.
Race Director
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From: northern california
C2 of Year Finalist (track prepared) 2019
My 1962, 327-300 is very hard to start after sitting a while. In checking the Carburetor I notice the Carburetor dry, so I assume the gas flows back to the tank. So it requires many attempts of starting until gas gets to the carburetor.Has any one installed a check valve to prevet flow back of gas to the tank? If so has it helped? Outside installing a electronic fuel pump are there any other solutions?
A long thread just last month dealt with this exact problem with many possible ways to mitigate it. In post #37 I described my meticulous and precision solution. Click the link below to go to this thread:
dry carb due to evaporation -- click here
Le Mans Master
Joined: Nov 2015
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From: Really Central IL Illinois
If you mean after setting for days, it is most likely evaporation.
If it occurs after shutting it off and waiting 20 minutes or so and it won't start, the fuel is boiling out of the carburetor and into the intake due to under hood temperature rising when the engine is not circulating coolant. It happens mostly in hot weather and especially with ethanol fuels. Pop the hood after a few minutes and see if the throttle bores and intake plenum are wet.
Have the exhaust cross over passages been blocked? I doubt you need the warmup they provide in FL.
Just thoughts.
If it occurs after shutting it off and waiting 20 minutes or so and it won't start, the fuel is boiling out of the carburetor and into the intake due to under hood temperature rising when the engine is not circulating coolant. It happens mostly in hot weather and especially with ethanol fuels. Pop the hood after a few minutes and see if the throttle bores and intake plenum are wet.
Have the exhaust cross over passages been blocked? I doubt you need the warmup they provide in FL.
Just thoughts.
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Joined: Jan 2003
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From: Central Arkansas
Your fuel line could drain back to the tank but your carburetor fuel bowls absolutely can not. The needle seat outlet creates a vacuum break and the bowl is vented so syphoning cannot occur. If the gas in your bowl was not evaporating your engine would start and run on the fuel in the bowl for a couple of minutes and easily resume flow from the tank to the carb in that time. It’s fuel bowl evaporation. Either prime the fuel bowl or spin the starter motor without touching the throttle for 2 to 4, five to ten second intervals to fill the bowl prior to starting the motor.
