Car sits too long and the floats dry up, have to pour gas down the carb several times to get it lit. This has been a problem for last couple months. Today it won't start period. Pull line to carb and crank over no gas coming out. Pull line to pump from tank, no gas comes from that line, but thats probably normal I figure.Lucky for me I only live a few miles from NPD and they have the right pump.(396/325 mechcanical)I'm not real convinced its the pump yet because every time in the past, once I got it started it ran perfect. Plus the ac comp is in the way and makes it a PIA to change out. Decide to do it and put in new pump, the dude starts right up. I know it seems elementry, but because it ran so good once running it just didn't seem to be the problem. Plus it wasn't leaking gas or oil. Any body have any ideas? I'm really just passing this along in case it hapeens to you. Al

fuel pump went out on my nova many years ago ,no leaks ,one day the car would run fine next would stall ,put gas down the carb would run fine again ,then stall later ,changed the pump finally no more trouble

It's happened to me at least half a dozen times over the years. No leaks, just the car quit running.

[This message has been edited by cjlandry (edited 02-01-2003).]

Mechanical fuel pumps can exhibit various types of wear. Over time, the check valves, which are just little rubber disks, become less capable at sealing reverse flow. This is especially true if the pump is operating at a low cycling frequency (low engine rpm) such as while cranking; approx. 150 to 200 rpm. The slow speed allows the check valves to leak backwards and doesn't allow the pump to 'pump' fuel towards the carburetor. At idling and higher rpm the pump 'pumps' enough to keep fuel in the float bowls.
This kind of symptom is an example of a mechanical fuel that hasn't 'failed' in the sense that anything is broken but it is definitely worn out.

Louie

Wouie, thanks for explanation, it all makes sense now. The pump looks pretty old, could be the original with 140k on it. Its always sumpim. Now I got to get the float problem fixed. Al