i have got a 1970 455 .on the first start of the day it always seems like my float bowl is empty.the car starts good for the rest of the day.it runs so good i dont want to rebuild the carb .is there any way the bowl can empty into the engine ?thanks alot

 

This is a common problem with Quadrajets. The fuel leaks around a pressed in plug which is used to fill a hole in the fuel bowl. This hole is there from the manufacturing process.

Some people try epoxy over the plugs to seal them. This is a short term solution for the most part as many epoxies are not resistant to fuel. Also, the epoxy must stay bonded to the carb body though all of the heating and cooling cycles that the carb sees.

I recommend contacting Cliff at http://www.cliffshighperformance.com/ He has a solution which involves installing screw in plugs. These plugs are coated with a fuel resistant grade epoxy.

 

The main well plugs are a well-documented leak point, but to be honest in almost 35 years of owning them I've never had this problem. Before you tear the carb apart, what fuel filter are you running? The factory paper filter has a check valve that should prevent fuel from leaking out of the carb. If you don't have the correct paper filter or if you've replaced it with an in-line filter, this may be your problem.

 

is the choke functioning properly? does it "snap" completely shut when you first hit the gas, before cranking? does the choke linkage and fast idle cam move freely or is it sticky/binding?

the location of the seat, in the bowl, prevents the bowl from being sucked dry due to a failed fuel filter check valve. the fuel level could be lowered somewhat, but, the bowl could not be drained dry.

the 704 series carb; that should be on the car, rarely has secondary well plug leakage problems-not impossible but not likely. the '68 and up spun-in plugs rarely leak, the '65-'67 cup-type plugs almost always leak. j-b weld will stand up to fuel, but, you must clean the well plug area positively clean and roughen up the area where you're going to apply the j-b weld. this gives the j-b weld something to hold on to.

there are external plugs too. is there any evidence of external leakage or casting porosity?

 

thanks alot you guys