Question on draining fuel
Thread Starter
Burning Brakes
Joined: Sep 2005
Posts: 769
Likes: 36
From: Goose Creek SC
Question on draining fuel
The car is a '68 Vette. I want to make sure there is no old gas in the system. The fuel tank is cleared, I just disconnected the line from the tank to the fuel pump and got nothing from either the tank side or the pump side. My question is, does that clear the line from the pump to the carb as well or is there a check valve situation in that fuel pump that could block the flow from the carb side?
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From: New Or-leens Loo-z-anna
Put a drip pan under the tank and have a fire extinguisher within reach.
Remove the rubber hose on the underside of the tank.
If no gas pours out of the metal tube shove a pieces of 12 ga. electric wire into the tube until gas pours out.
If no gas pours out the metal gas strainer could be ruined and you need a new one.
Remove the gas line from the inlet fitting on the fuel pump.
Tape a clear 1 qt. container tightly onto the gas line that was cdisconnected from the fuel pump inlet.
Lightly blow short bursts of air pressure into the disconnected fuel line rubber hose you removed from the tank.
If gas begins to pour out into the container you have cleared the metal line.
If NOTHING FLOWS OUT THE METAL GAS LINE is ruined and you need a new metal line.
Remove the gas line from the carb inlet...also remove the same gas line from the carb outlet fitting.
Tape the clear container to the lower end of THAT line and blow short bursts of compressed air into the top of that line to cleat the trash out of it.
DO NOT BLOW compressed air into the fuel pump or carb inlet...you could ruin both components.
LET US KNOW HOW THE ABOVE TEST TURN OUT.
Then you can deal with the carb and fuel pump later.
Remove the rubber hose on the underside of the tank.
If no gas pours out of the metal tube shove a pieces of 12 ga. electric wire into the tube until gas pours out.
If no gas pours out the metal gas strainer could be ruined and you need a new one.
Remove the gas line from the inlet fitting on the fuel pump.
Tape a clear 1 qt. container tightly onto the gas line that was cdisconnected from the fuel pump inlet.
Lightly blow short bursts of air pressure into the disconnected fuel line rubber hose you removed from the tank.
If gas begins to pour out into the container you have cleared the metal line.
If NOTHING FLOWS OUT THE METAL GAS LINE is ruined and you need a new metal line.
Remove the gas line from the carb inlet...also remove the same gas line from the carb outlet fitting.
Tape the clear container to the lower end of THAT line and blow short bursts of compressed air into the top of that line to cleat the trash out of it.
DO NOT BLOW compressed air into the fuel pump or carb inlet...you could ruin both components.
LET US KNOW HOW THE ABOVE TEST TURN OUT.
Then you can deal with the carb and fuel pump later.
Thread Starter
Burning Brakes
Joined: Sep 2005
Posts: 769
Likes: 36
From: Goose Creek SC
Everything from the tank to the carb is new on this car. It briefly had a small amount of fuel in it several years ago for an engine start test. I know the tank is empty and the fuel line from tank to pump is empty and clean. I just want to know if any fuel that may have been between the pump and carb would have drained out, assuming there was any in there, when I disconnected the fuel line from the pump. Or could there still be some fuel above the pump, trapped between it and the carb. I don't want to disconnect the fuel line that runs between carb and pump if not necessary. Hard to get to and hard for me to see with limited vision.
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Can't invision any possible way to clear old fuel without disconnecting line and blowing it out!
I would run carb cleaner through it as well if fuel has sat in it for years.
On customer jobs where fuel has sat in lines for 2 or more years I replace all lines. Just to much work to clean them. At 163 dollars an hour. It just makes sense to replace all fuel lines and fittings.
Just not worth chancing it. Sorry if it's a pain. But if you left stale fuel in lines that's the price.
I would run carb cleaner through it as well if fuel has sat in it for years.
On customer jobs where fuel has sat in lines for 2 or more years I replace all lines. Just to much work to clean them. At 163 dollars an hour. It just makes sense to replace all fuel lines and fittings.
Just not worth chancing it. Sorry if it's a pain. But if you left stale fuel in lines that's the price.
Melting Slicks
Joined: Oct 2012
Posts: 2,156
Likes: 273
From: Dunedin NZ.
Everything from the tank to the carb is new on this car. It briefly had a small amount of fuel in it several years ago for an engine start test. I know the tank is empty and the fuel line from tank to pump is empty and clean. I just want to know if any fuel that may have been between the pump and carb would have drained out, assuming there was any in there, when I disconnected the fuel line from the pump. Or could there still be some fuel above the pump, trapped between it and the carb. I don't want to disconnect the fuel line that runs between carb and pump if not necessary. Hard to get to and hard for me to see with limited vision.
Thread Starter
Burning Brakes
Joined: Sep 2005
Posts: 769
Likes: 36
From: Goose Creek SC
Why not just disconnect the fuel line from the carb and direct it into a container then crank the motor for a few seconds. You could disconnect one of the low tension wires from the ignition coil to stop the engine trying to start. If you're worried about stale fuel in the line what about the carb fuel bowl?
