77' Ford F100
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77' Ford F100
I am having trouble with my 77' F100 starting, it'll crank and crank, but wont start. It'll start up for a couple seconds if I pour gas down the carb and then die. I just replaced the fuel pump today, could it be the fuel sending unit inside the tank? If so, what's the easiest way to drop the tank, last time I dropped the fuel tank it took weeks to get it back on.
Cargo Master
Joined: Jul 2015
Posts: 2,068
Likes: 138
From: tucson
First look down the carburetor and operate the accelerator. You should see gas squirting in the venturis. If not, disconnect the fuel line from the carb and with the end in a container, turn on the key and see if fuel flows.
If not, make sure you have voltage to the pump.
If not, make sure you have voltage to the pump.
Laughing Gas
Joined: Apr 2018
Posts: 1,244
Likes: 12
If you have a mechanical pump, no voltage needed. I take it this problem started before you replaced the fuel pump?
As stated above, take the fuel line off the carb and put it in a container. If your fuel pump is mechanical, turn the engine over in order to work the pump. If fuel is coming out, your problems lie elsewhere.
If you aren't getting fuel, it could be a hole in your fuel line, a rotted out pickup tube, a line full of rust, etc. Check all the stuff that doesn't require you to drop your tank.
You could also try hooking the inlet side of your fuel pump up to a line going to a gas can. Just be sure all the gas from your tank doesn't leak out from the regular line. If it runs off a gas can your have trouble somewhere with the line or the tank. If it doesn't pump the gas from the can... take the pump off. Pump the lever by hand. does it pump gas with you pumping the lever by hand? If so, try to take a peak and see what the part of your cam that operates the pump looks like. does it show signs of wear? It could be that your pumps are fine, but the cam is worn and will no longer actuate the pump lever.
As stated above, take the fuel line off the carb and put it in a container. If your fuel pump is mechanical, turn the engine over in order to work the pump. If fuel is coming out, your problems lie elsewhere.
If you aren't getting fuel, it could be a hole in your fuel line, a rotted out pickup tube, a line full of rust, etc. Check all the stuff that doesn't require you to drop your tank.
You could also try hooking the inlet side of your fuel pump up to a line going to a gas can. Just be sure all the gas from your tank doesn't leak out from the regular line. If it runs off a gas can your have trouble somewhere with the line or the tank. If it doesn't pump the gas from the can... take the pump off. Pump the lever by hand. does it pump gas with you pumping the lever by hand? If so, try to take a peak and see what the part of your cam that operates the pump looks like. does it show signs of wear? It could be that your pumps are fine, but the cam is worn and will no longer actuate the pump lever.
FTE Legend
Joined: Nov 2015
Posts: 30,915
Likes: 4,123
From: Angier, NC
If you have a mechanical pump, no voltage needed. I take it this problem started before you replaced the fuel pump?
As stated above, take the fuel line off the carb and put it in a container. If your fuel pump is mechanical, turn the engine over in order to work the pump. If fuel is coming out, your problems lie elsewhere.
If you aren't getting fuel, it could be a hole in your fuel line, a rotted out pickup tube, a line full of rust, etc. Check all the stuff that doesn't require you to drop your tank.
You could also try hooking the inlet side of your fuel pump up to a line going to a gas can. Just be sure all the gas from your tank doesn't leak out from the regular line. If it runs off a gas can your have trouble somewhere with the line or the tank. If it doesn't pump the gas from the can... take the pump off. Pump the lever by hand. does it pump gas with you pumping the lever by hand? If so, try to take a peak and see what the part of your cam that operates the pump looks like. does it show signs of wear? It could be that your pumps are fine, but the cam is worn and will no longer actuate the pump lever.
As stated above, take the fuel line off the carb and put it in a container. If your fuel pump is mechanical, turn the engine over in order to work the pump. If fuel is coming out, your problems lie elsewhere.
If you aren't getting fuel, it could be a hole in your fuel line, a rotted out pickup tube, a line full of rust, etc. Check all the stuff that doesn't require you to drop your tank.
You could also try hooking the inlet side of your fuel pump up to a line going to a gas can. Just be sure all the gas from your tank doesn't leak out from the regular line. If it runs off a gas can your have trouble somewhere with the line or the tank. If it doesn't pump the gas from the can... take the pump off. Pump the lever by hand. does it pump gas with you pumping the lever by hand? If so, try to take a peak and see what the part of your cam that operates the pump looks like. does it show signs of wear? It could be that your pumps are fine, but the cam is worn and will no longer actuate the pump lever.
look at the lever and you can see what side the lever hits the cam lobe and make sure it is on the right side of the lobe.
Dave ----
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