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Gas Dumping Out on Ground Under Car

tony barnhill

Great Pumpkin - R.I.P
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So, I'm piddling with my '74-1/2 GT & left the ignition on while piddling...

...the fuel system never pressurized & dumped gas out on the garage floor from the anti run-on valve vent hose (#64 in bottom diagram below)....apparently, once the fuel bowls are full instead of pressurizing the system & causing the pump (brand new) to stop pumping, the pump continues pumping & the excess gas is going through the overflow hose at the carbs (its the unmarked pipe/hose combination connecting the 2 carbs in the top diagram) ending up in the charcoal cannister (#60 in top diagram below) then from there via the run-on valve hose to the cannister (#66 in bottom diagram) through the anti run-on valve (#61 in bottom cannister) & into the anti run-on valve vent hose then onto the floor.

So, correct me if I'm wrong...I've either got float problems (I just rebuilt both HIF-4 carbs) or a leak somewhere in the fuel system that's allowing enough air in the system so it can't pressurize...does that sound feasible? Or, should I focus on what I might have done wrong in the float bowls?

MGB-017.gif
 
I'd go with the float bowl investigation to start, Tony. If the needle valves properly closed, the fuel pump should have shut off.
Or, there's a problem with the fuel pressure.
Doing the floats on HIF's make you appreciate the HS4 configuration!
Jeff
 
I knew that - was just hoping I didn't have to remove the carbs again...oh well, tomorrow's another day!
 
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