Thread: No pump shot

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Geez, seems like im having lots of problems lately. My buddy let me drive his Chevelle the other day, I pressed on the gas and the engine flat out shut off and refused to start. I checked the carb (old holley 4 barrel 4160), totally dry, and no pump shot. I guessed it was a bad fuel pump (mechanical). So I disconnected hose at carb, cranked the engine and fuel shot 10 feet across the driveway. The pump is good. Reconnected the hose, poured some fuel into the carb, it ran for 5 seconds and shut off again. Whats the deal? Bad accelerator pump? Should he just dump it and install a new carb?

Rebuild the carb -

Or if you prefer to piece-meal it -

First to check is the internal fuel filter, if it has one.
You could remove it temporarily to eliminate that as an issue.

Next, the float needle valve that could be 'varnished' closed.
If that's the issue, a full carb cleaning is probably needed.

Then check the accelerator pump shot.

Before disassembly, light hammer taps may free a stuck float valve.

Need more info. Was it running for a while before it quit, or did you just get it going after it sat for some time? Like, long enough for the gas in the carb to evaporate and gum everything up?

We were out driving all morning. Stopped for lunch, started her up again and pulled out of driveway, hit the gas, and poof...just shut off. No fuel being shot into carb at all.