1974 C10, 350 v8, No fuel to carb

[Wili74]

I'm working on a 74 c10 with a stock 350. I'm having lack of fuel to carb problems. Replaced the fuel pump today, but only small amount of fuel will pump up to  the clear plastic fuel filter, engine won't run. I poured a little fuel in the carb a couple of times,  it started and it ran for a few seconds. Siphoned some gas out of the fuel  line before the pump, so its not clogged. Could this "cannister thing" be preventing normal flow from the tank to the pump? Does fuel go through the "cannister thing" ? I tried to test the old and new fuel pump after removing them and running a rubber line from the IN port to a bowl of water and manually operating the pump actuator. Neither pump "pumped"  water out. Any thoughts? I think I'll get another pump and try it.

[Wili74]

 I'm working on a 74 c10 with a stock 350, one fuel tank. I'm having lack of fuel to carb problems. Replaced the fuel pump today, but only small amount of fuel will pump up to  the clear plastic fuel filter, engine won't run. I poured a little fuel in the carb a couple of times,  it started and it ran for a few seconds. Siphoned some gas out of the fuel  line before the pump, so its not clogged. I tried to test the old and new fuel pumps after removing them, running a rubber line from the IN port to a bowl of water and manually operating the pump actuator. Neither pump "pumped"  water out. Any thoughts? I think I'll get another pump and try it. I can manually move the push rod up and  the cam pushes it down when I crank engine without the pump in place. I'd appreciate any help you can provide.

[VileZambonie]

You cannot manually pump it nearly fast enough for it to provide any type of valid test. It needs to be installed on the engine, pushrod in place. The canister thing is called the charcoal canister or vapor canister and unless someone incorrectly routed your lines it does not sound like it is your issue. Loosen the gas cap and see if it makes a difference in fuel flowing to the pump. Check for kinked or collapsed hoses, make sure you're not out of gas, try to siphon fuel from the feed line.

[Wili74]

Thanks. I installed another pump (#2) today. Still no gas to filter/carb. Checked gas line around pump back to firewall, then crawled underneath and followed gas line back to tank. Nothing obvious. Good idea taking the gas cap off, I'll try tomorrow and also try to get some gas to flow from the feed line to the pump from the tank with a siphon. Starting to wonder if my push rod or the actuator cam are worn. Could mean an electric pump  is a solution I'll need to pursue. Maybe I can borrow a pressure gauge. Will a gauge measure air pressure or does there have to be gas flowing to measure pressure?

[VileZambonie]

You need to check for volume, not pressure so if nothing is flowing there is no point in going down that road. In order for the pump to pump, fuel needs to free flow from the tank to the pump. If this does not happen then that's where you need to be looking. Make sure the hoses on top of the tank aren't kinked or collapsed.