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Could It be my Fuel Tank / Fuel Line?

3K views 4 replies 4 participants last post by  boatbob2 
#1 ·
Ever since I got my car I've had a cold start problem with it. About 10 minutes after sitting overnight or for a long time the engine acts fuel starved for a few minutes. I've worked with Edelbrock technical support, replaced the HEI module and spark plugs. Had the timing checked and replaced the fuel filter. I even put a new carburetor on it but so far, nothing has eliminated this problem. Once the car has been started and run for about 15 minutes, it starts perfectly and runs fine all day long until the next cold start. The car is a glass bodied 37 Ford on what I believe is a modified 37 frame. It has a stainless gas tank that sits between the rear frame rails. The fitting for the gas line is located about midway between the top and the bottom of the tank on the right side. The fuel line is routed in an upward direction from where it connects to the tank (about 2-3 inches) and runs along the top of the frame rail to the the mechanical fuel pump on the engine. After looking at this I'm beginning to wonder if some of the the fuel is draining back into the tank after the car sits for an extended period and then causing it to act like it's running out of gas until the line is completely filled again. If that's the case, what are my options? Can I install in in-line electric fuel pump? Are there any kind of check valves that would keep gas in the fuel line from draining back into the tank? Could this problem be symptomatic of a bad mechanical fuel pump or does this sound like fuel line routing / gravity issue?
 
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#2 ·
fuel drain back problem ?

After it has sit, try moving the carb. linkage while watching down the carb. to see if its pumping (squirting) gas. You may have to try it 2 to 4 time. If it runs out of gas, you may have a bleed back to the tank. If you go with an electric pump, you still have to turn on the pump and wait for it to prime the carb. before trying to start it. A check valve would stop it from bleeding back if installed at the tank. You also might try (after sitting) pouring a little gas down the carb. and try starting it. If it fires up the you know it a gas problem. If it doesn;t you better look further. lol
 
#3 ·
lanier ledford said:
After it has sit, try moving the carb. linkage while watching down the carb. to see if its pumping (squirting) gas. You may have to try it 2 to 4 time. If it runs out of gas, you may have a bleed back to the tank. If you go with an electric pump, you still have to turn on the pump and wait for it to prime the carb. before trying to start it. A check valve would stop it from bleeding back if installed at the tank. You also might try (after sitting) pouring a little gas down the carb. and try starting it. If it fires up the you know it a gas problem. If it doesn;t you better look further. lol
The problem doesn't begin immediately after a cold start. It will start and run OK after sitting overnight. It acts like it's running out of gas about 7-10 minutes after a cold start.
 
#4 ·
I would look at the fuel pump. If it starts up and runs for a while, that means your float bowls are full and it probably runs until they are empty. You fuel pump is probably letting the gas run back to the tank and is loosing it's prime. The fuel pump has a built in check valve to keep fuel in the line to the carb. If this is wore out or a piece of dirt under it, it will allow the gas to run back to the tank and if you pump is weak it will take a long time to catch up. Unhook line to carb before you start it and see if gas is present. It should and may be under pressure, if not , put line into a safe container and crank over engine and see how long it takes to get fuel. Be careful with this so you don't start a fire!!!!!! Or just try a new pump. Just my thoughts. :thumbup:
 
#5 · (Edited)
fuel problem....

HI,i would remove the fuel inlet hose at the fuel pump,,get the proper size rubber hose,put a fitting on the hose,screw it into the fuel pump, open the fuel fill door,remove gas cap,stick hose into tank through fill,make sure the hose is NOT on the bottom of the tank, you are by-passing entire fuel system, ,duct tape the hose to the side of the car,and also at fill spout.remove fuel line at carb,using a clean milk jug,put line into jug,have someone turn engine over,careful of fire,time to fill jug 1/4 way,if ok, re-attach hose to carb. drive the car.if ,it works like it should,you have a problem with either,fuel tank,(crud getting into fuel output line,or fuel line itself. possibly,also,fuel bowl of carb is dirty ive never seen a fuel tank outlet like you describe,i always have them made with a top fuel exit fitting.
 
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