Need help with Fuel System 67 C20 327

[71GMCNC]

Hello all,

Ok just to make sure I am not missing anything here as the system seems quite simple. I am trying to get my C20 running. It runs when I use starting fluid but then stops.

I have undone the fuel line into the carb and then turn her over and get no fuel coming out.

I traced past the fuel pump to a rubber hose that connects the pump to the line going to the in-cab tank. That hose was collapsed and was at a weird angle to I replaced and put an inline filter while there. Still no gas present inline.

I undo the fuel line going to the fuel sender and blew out the line. All is cear however no gas in the line.

That brings me to the tank... I replaced the tank due to excessive rust and failed sender and put a new tank and sender in.

So with everything connected other than the line going into the carb and I crank and crank to get the fuel into lines and to the carb yet no matter how much i crank no fuel comes out. I have killed a battery doing this.

So this would leave the fuel pump being bad correct? Sorry, I am electronic savvy and not mechanical. I am new to being a backyard mechanic.

Any input is greatly appreciated.

On a brighter note I ordered kick panel speakers and estuchean (spelling?) for the window crank and door handles interior for the GMC.

[mclairmo]

You will also kill the starter if you crank it too much without letting the starter cool down. I know because I did this before. Replace the fuel pump, its cheap and the diaphragm in there can easily dry our and/or rupture. Check pushrod, too. Also, be sure that the hard line from the sender to the pump is clear. Old gas can varnish and clog hard lines. Also, be sure the line from the pump to the carb is clear.

[cdowns]

to eliminate the tank as the problem put a hose in a tank of gas connected to the inlet side of the pump// there' should be a rubber line going from the frame to the gas line that enters the cab it's about even with the rear door post on the passenger side of the truck

[Arizona oldguy]

Ya it sounds like the fuel pump is not pumping fuel, one of our brothers mentioned the push rod, this rod runs off of the cam and actuates the lever on the pump. When you pull the pump off the rod will or should fall down, when you go to put the new pump in you will not be able to cause the dad- gum rod is in the way. Now there are two bolt holes in the front of the motor, down low almost in line with the balancer, one of them is a passage way to the fuel pump push rod, it may and should already have a short 3/8 inch bolt in it, if you can find it you can put a longer bolt in the hole, it will bottom out against the push rod and hold it in place. Now don't get western with it and tighten it to much or you will mess up the push rod, it only takes a little pressure to hold the rod up and keep it from sliding down. Hope I have helped and not confused you to much. Good Luck

[71GMCNC]

Ok problem was the fuel pump. I replaced it last night and she fired right up. Got to adjust the carb a bit but she sounds good. That pushrod was a pain. I had to bump the motor to get the cam ecentric in the right spot so the rod would go up all the way. I held it up with a thin screwdriver and got the pump on. Thanks for the replies. I am now an expert on that fuel system...lol