I popped for a new 1407 and think I got a bad carb? This thing leaks (bleeds down) dry in three days? The old one --same 1407 had plenty of gas after a three day sit. Is it normal for zero accelerator pump action after a three day sit? You have to turn it over for perhaps a full minute to pump gas. When you pull the lid and prime it--it starts right up. I wonder if the mechanical fuel pump is leaking and the supply line is also emptying? By the way, its on a Chevy 454 but its in a Buick Streetrod. Thanks
if that's a performer carb and not a q-jet style than there are no gaskets below the fuel bowl to leak. The only way it could be leaking down is through the baseplate or through the fuel line. Are you sure it's not just evaporating off with the summer temps?
My Edelbrock carb leaks down, also. Takes a Bunch of cranks to get the gas back in the bowls to fire up after a few days sitting. Takes a lot after 5+ days of sitting.
I think it's just evaporating out of the bowl. I have had this problem in the past with my Edelbrock carb. I'd avoid pumping it, that's just going to wear out the accelerator pump piston seal. I usually just dump about 10 ccs (about 3 teaspoons) of gas into the carb and it starts and runs...raggedly, then picks up. I drive my car about 20 miles once a week, just to keep it up.
FUNNY The car came with a 1407 that would hold some gas for 5 days? It would run a litte rough but not require extended cranking. I might just move over to an electric pump.
This new gas doesn't stay around long in a carb. It seems to evaporate in a couple days and if you let it sit long enough it'll just dry up and leave behind deposits.
Recently, I removed the Q-jet from my engine after shutting it down and put it on the work bench in the shop. Every morning when I got to work, I moved the throttle all the way open once, or full accl pump shot. On the 5th day the pump shot was just a dribble. I guess that's about the best case scenario for how long the carb can sit and still have enough fuel to start the engine without excessive cranking to put some fuel back in the bowl....Cliff
:gp: That's actually a really good experiment. Glad to know we have a pretty definite timeline on how long the gas lasts. Wonder if the winter blend lasts longer or if the cold weather makes it evaporate any slowero No:
My test didn't involved heating up the carb or having it sit on a hot intake after shutdown, which may cause more fuel to evaporate out within the first few hours. Working the throttle also emptied the bowl a little faster than just sitting there. I don't have any issues right to start with, as I use and electric pump, pretty much a manditory deal with my car, as mechanical pumps can't keep up with the engine anyhow.....Cliff
Thought?? when I changed from old 1407 to new I put in a cheap see-through fuel filter. New car (to me) I wanted to see whats coming up from the tank. Its plastic and definately a smaller capacity than the orginal metal one and I'm sure conducts more heat than the original. I'll switch back and try it.
