Topic: Qjet leaking overnight
in Forum: C3 Fuel, Emission Control, and Exhaust Systems
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Houston, TX - USA
Joined: 2/7/2008
Posts: 93
Vette(s): 1970 454 4 speed A/C power everything else
I have the original 7040205 on my car with a recent rebuild using quality parts from Cliffs high performance carburetors.
I have drilled, tapped, and epoxied the well plugs both primary and secondary, but it still leaks overnight and leaves a puddle in the intake. The only clue is the primary well plugs look wet, but I can't believe they would still leak after being drilled, tapped and plugged with screw in plugs with epoxy all over the threads.
Any other source of leakage?
Right now I have the carb apart but I have fuel in the bowl waiting for evidence of a leak.
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Well...when I first saw the topic, I immediately thought "Welch plugs in the bowl", but...
Only thing I can think of would be a crack in the fuel bowl, if the leak is not coming from the plugs....
A crack may not be easily visible unless the fuel bowl is hot, so you may not be able to find it....
Only thing I can think of would be a crack in the fuel bowl, if the leak is not coming from the plugs....
A crack may not be easily visible unless the fuel bowl is hot, so you may not be able to find it....
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Former Member
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Houston, TX - USA
Joined: 2/7/2008
Posts: 93
Vette(s): 1970 454 4 speed A/C power everything else
I checked the carb this morning and I could tell the level of fuel was down in the bowl, but no evidence on the paper I placed underneath it. I guess some has evaporated. The well plugs appear dry on the bottom.
My theory is you may be right on the crack in the bowl and when it heats up the crack gets larger and leaks and when it cools down it stops leaking. When I took the carb off the other day the bowl was about half empty and the puddle in the intake explains where is went. I figure when I turn the engine off, it's hot so it leaks into the intake until it cools and then stops, so I'm losing about half the fuel in the bowl.
So I guess while I'm driving the crack opens up and the car runs worse until it starts to effect idle and I have to hit the gas to keep it running at times.
I have the Holley Qjet replacement, I guess I can try it and see how the engine runs.
in Forum: C3 Fuel, Emission Control, and Exhaust Systems
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