235 fuel pump truck vs. car ?

Looking for advise about my lack of fuel. Have a 54 235 in my 49 GMC.
Replaced the fuel pump at the advise of the PO. I looked up the part # and its a Bel Air pump which has a differant part # from that of a 54 PU
I've tried priming the pump. Took it off and pumped it by hand and it seemed to work. But no go getting gas to the carb.
I figured it might take some effort to get going but even after filling the fuel bowl it runs till the bowl level drops. It wont "pump"
Maybe its pumping but not enough? a bad "new" one ?
Or am I over looking something basic?
Could the truck pump really be differant ?

 

make sure the fuel line going to the tank isnt blocked or kinked anywhere

 

disconect the fuel comming from the gas tank at the fuel pump. take the gas cap off and blow air with a compressor into the gas tank the gas should come out, if it doesnt blow compressed air from the disconected gas line toward the gas tank with the cap off PM ME I HAD A CARDBOARD GAS CAN CAP LINER SEAL IN MY GAS TANK AND IT PLUGED THE TANK ON AND OFF

 

Thanks pugs ! We pulled the line, just to be sure. Its not coming from the tank its just not worth the risk from old dirty watery fuel. So I have a temporary rubber hose sticking into 4-5" of gas.
Should it not draw up to the pump from the temporary container ?
Same as a pick up tube I would think.

Here is a couple pics, obvious difference in the 2 pumps

 

Try opening up the new (is it NOS?) fuel pump to see if the diaphram is cracked. If it's been on the shelf for 50 years maybe the action tore the rubber.

 

Not for nothing, but it took me three fuel pumps from Napa before I got a good one for my '53 Bel Air (same fuel pump as you). Where's yours from?

 

This is from the shop manual for a '55 chevy pickup with a 235 (same pump). These are instructions for reassembling the fuel pump. Check out number six...

http://chevy.oldcarmanualproject.com/shop/1955truck2/55ctsm06m32.htm



Here's the beginning of the section on the fuel pump. Keep clicking "next page" at the bottom to go through the entire fuel pump section in the manual...

http://chevy.oldcarmanualproject.com/shop/1955truck2/55ctsm06m29.htm




None of this may help, but more info never hurts. Let us know what you find out.

 

put the line going into the pump into a gas can with fresh fuel, turn the engine and see if it starts.