I have a 1968, 31 commander, 327s,after not starting for a week or longer, gas seems to go back down the line,has new fuel pumps, and lines, best way to get fuel back up to carb, without cranking engine for ever
Do you have one way check valves in the lines, usually at the tank or strainer fittings? A common cause especially if you have Rochester carbs is the well plugs in the main body are allowing the float bowl to drain when sitting. This is a very common problem with the Q-jets.
More than 2 days without running my carbs are dry. True for the original and new engines. My solution is a small wash bottle, maybe 50 to 75mls. 25 or so in overflow spout, a good squirt down a primary, reattach the flame arrestor and fire it off. While the first warms (yes exhaust was checked for water flow) the other engine is given the same treatment. Some time ago Dick Morland posted a long dissertation on adding supplemental electric fuel pumps to ensure carbs were full and prevent fuel starvation at WOT.
On most carbed engines it's normal for fuel to evaporate out of the float bowls after a few days. It shouldn't take more than a couple of seconds to get fuel back into the carb though. If you're needing to crank for an unusually long time then the fuel pump may be leaking back or you may have an air leak in the fuel lines. Most mechanical fuel pumps move air quite effectively, so even starting from dry lines and filters doesn't take long. I did it after a carb rebuild and some fuel system changes over the winter. Both engines had fuel pulled through the lines, filters, and pushed up to the carbs after about 5 seconds of cranking.
For my 454s with Quadrajets, typically up to about a week they'll start with a couple pumps of the throttle and a turn of the key, as there's still enough fuel to get an accelerator pump shot and have it get more fuel to the carb before it runs out after start. If they sit for 2+ weeks it'll often take a few seconds of cranking and then a throttle pump before they fire.
If it's got Quadrajets, check for well plug leakage as Craig mentioned. It's much less common on the later year carbs, but I'm pretty sure 68 was before they improved on that issue.
Do you have one way check valves in the lines, usually at the tank or strainer fittings? A common cause especially if you have Rochester carbs is the well plugs in the main body are allowing the float bowl to drain when sitting. This is a very common problem with the Q-jets.
More than 2 days without running my carbs are dry. True for the original and new engines. My solution is a small wash bottle, maybe 50 to 75mls. 25 or so in overflow spout, a good squirt down a primary, reattach the flame arrestor and fire it off. While the first warms (yes exhaust was checked for water flow) the other engine is given the same treatment. Some time ago Dick Morland posted a long dissertation on adding supplemental electric fuel pumps to ensure carbs were full and prevent fuel starvation at WOT.
On most carbed engines it's normal for fuel to evaporate out of the float bowls after a few days. It shouldn't take more than a couple of seconds to get fuel back into the carb though. If you're needing to crank for an unusually long time then the fuel pump may be leaking back or you may have an air leak in the fuel lines. Most mechanical fuel pumps move air quite effectively, so even starting from dry lines and filters doesn't take long. I did it after a carb rebuild and some fuel system changes over the winter. Both engines had fuel pulled through the lines, filters, and pushed up to the carbs after about 5 seconds of cranking.
For my 454s with Quadrajets, typically up to about a week they'll start with a couple pumps of the throttle and a turn of the key, as there's still enough fuel to get an accelerator pump shot and have it get more fuel to the carb before it runs out after start. If they sit for 2+ weeks it'll often take a few seconds of cranking and then a throttle pump before they fire.
If it's got Quadrajets, check for well plug leakage as Craig mentioned. It's much less common on the later year carbs, but I'm pretty sure 68 was before they improved on that issue.