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My dad and I built the general lee, a 69 dodge charger. No major problems except that when it get really hot outside, like 90 degrees and up, the fuel pump starts acting up. The pump is running, you can hear it, but no gas is coming out. We took the pump apart and everything looks fine, but we are out of ideas. Help! My baby would like to get shown off this summer!
 

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My dad and I built the general lee, a 69 dodge charger. No major problems except that when it get really hot outside, like 90 degrees and up, the fuel pump starts acting up. The pump is running, you can hear it, but no gas is coming out. We took the pump apart and everything looks fine, but we are out of ideas. Help! My baby would like to get shown off this summer!
is it an in-line fuel pump? or is it tank mounted? may have a clog in a line or a tiny pin hole that you may have missed causing it to lose suction.
 

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First, welcome to the Z! Second, we want pictures of the General!

OK, I figure on a '69, you have a mechanical fuel pump. I've never had the issue you are having, but I recall hearing about problems with the fuel vaporizing in the fuel lines during hot weather on some older cars, causing this problem. So I broke out my #1 diagnostic tool, Google.

From Wikipedia: The pump creates negative pressure to draw the fuel through the lines. However, the low pressure between the pump and the fuel tank, in combination with heat from the engine and/or hot weather, can cause the fuel to vaporize in the supply line. This results in fuel starvation as the fuel pump, designed to pump liquid, not vapor, is unable to suck more fuel to the engine, causing the engine to stall. This condition is different from vapor lock, where high engine heat on the pressured side of the pump (between the pump and the carburetor) boils the fuel in the lines, also starving the engine of enough fuel to run. Mechanical automotive fuel pumps generally do not generate much more than 10-15 psi, which is more than enough for most carburetors.

Sounds like your problem right there, but it's gonna take someone with a bit more experience than me to give you a solution. Maybe replacing the mechanical pump with an electric one?
 

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Is your fuel pump stock or is it an aftermarket? You may want to try the high flow fuel pump if you don't already have one in there....Even though you may have checked the fuel lines, filter, etc, there still could be a partial blockage causing these problems....The idea Smitty has of the electronic fuel pump may be a good one....but if you are trying to keep the general a stock charger...try a higher flow pump....Just my $.02......Our '64 Dodge Polara did that....we replaced the fuel pump with an Edelbrock high flow....fixed it right up for us....
 

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The pump is running, you can hear it....
Now I'm starting to wonder if you have an electric pump, otherwise you wouldn't be able to hear it. Time for smarter mechanics than me.

Great looking Gen Lee, though! Y'all did a great job! What's under the hood?
 

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Even though carbureted fuel systems don't require as much pressure as EFI, the pumps can still wear out. I think Smitty might be on to something. There's less stuff to go wrong on those oldies, so if your lines are ok then the pump would be my next suspect.
 

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All I hear is the General Lees horn when I see your pic! Nice Ride!
 

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Your car is awesome, I hope to see more pics of it around here! About the fuel pump, I would be no help, but it looks like some other members have already come up with some solutions for you :)
 

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OK, I figure on a '69, you have a mechanical fuel pump. I've never had the issue you are having, but I recall hearing about problems with the fuel vaporizing in the fuel lines during hot weather on some older cars, causing this problem.
X2 on this!

This is a VERY common issue on piston powered aircraft (I'm an aircraft mechanic so I know a thing or two about these vehicles). Fuel pumps are almost always engine driven and gear-type (mechanical pumps). The high temperatures cause the fuel to vaporize which creates little bubbles in the fuel line. This is less of a problem when the engine is at a higher RPM because the pump spins faster and creates more fuel pressure.

The solution? A secondary electrically driven fuel boost pump. On aircraft, it is typically only used during ground operations (taxiing), takeoff (for safety reasons in case the mechanical one fails), and landing (for the same reason). In your case, an electrically driven fuel pump (in-line) near the fuel tank should solve your problem. If you want, you can put a switch on it and only use it when you're having problems to help prolong the life of the motor.
 
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