Ok - so progress has been made, but we're not quite there yet. I installed a new 25 gallon Spectre tank meant for a 76 C30 at the rear of the frame behind the axle. I am using the Spectre sending unit specified for that tank, and then an inline Airtex E8251 pump just forward of the tank mounted to the frame rail (I picked that pump after googling and finding it recommended for use in these old trucks). I still have the mechanical fuel pump (new) installed. I have the fuel pump running off a fuse panel - basically it turns on when I turn the key on - there is no low oil pressure or high fuel pressure switch installed (I didn't think it was going to be necessary). Unfortunately - the electric fuel pump is overpowering the float and blowing fuel everywhere. Now why did I install an electric pump? Well - it seems that my mechanical pump is not pumping enough at all. I can prime the bowl with the electric pump, yank the fuse when I see it flooding, and then start the engine, and it will seem to run only long enough to drain the carb bowl, then it dies. I can then verify the bowl is empty by looking down the throat and lifting the throttle rod - and seeing that I do NOT get a squirt of fuel.
So what's the matter with my setup? I was sure the electric fuel pump was going to solve my low fuel pressure woes, but now I have the opposite problem.
