Originally Posted by 85impala
Wow thanks for the info, I'll try that soon and post back here with my results.
The newer Q-jets almost never leak at the well plugs. If they ARE leaking, the engine will either take a lot of cranking before it starts or will start then immediately stall until it's cranked or run enough for the float bowl to refill.
Below is what epoxy looks like after a brief exposure to gasoline. Marine Tex epoxy is supposed to last better but I've never used it to say first hand, and there are several types- Ruggles
has info on Marine Tex if you ever wanted to try it (click on image for article on rebuilding a Q-jet):
And here's those cheesy little pads the rebuild kits include, before and after being installed for a while. Utterly useless:
The method that has the best track record for staying
fixed (no rubber o-rings or epoxy) is to tap the plug holes for a threaded plug as shown below:
There's a chance the fuel pump diaphragm is bad as DV said. Or that the fuel pressure is too high (you need ~4-5 psi). There's also a chance the needle and seat isn't shutting off the flow. Or that the float has become fuel logged and that is causing the float level to be too high. One thing that will sometimes help is to use a carb filter (the one that's inside the fuel inlet housing that the fuel line attaches to) with the spring loaded check valve on it, not the type w/o the check valve- either will fit.
In any event, if the carb is allowing fuel to get into the engine when it's shut off, I'd want to be real
sure this wasn't also happening as you are driving- if it is, the excess fuel will wash the oil from the cylinder walls and that leads to rapid ring and bore wear. You might want to pull a couple plugs to check them for having black dry deposits- meaning a too-rich mixture.