1979 chevy step van 350 new fuel pump rebuilt carburetor wont sta

Check the gears on the distributor.

Hi, if you fitted new pump have you checked that it is functioning,are the fuel lines clear of detritus. The fuel lines may be blocked somewhere. Girst thing is probably to check the pump works and is pumping petrol tpwards engine compartment.If it does then there is, obviously an issue between the pump and the carb.

The injectors are mounted in a throttle body.
If you have normal fuel pressure at the injectors, they may not be getting power and ground from the engine computer.

it is your carburetor the fuel float is set to high and probably leaks. If it older than 10yrs old and has never been rebuilt . do that if you want to save yourself a bunch of time and little more money make the investment of a Brand New not rebuilt. if you get the carb manufactor specs matched to your motor , Out of the box, it will be very close to being on the money .

chk in line fuel filter for obstruction, also could be a lot of sediment in the tank clogging up the filter. Hope this helps you resolve your problem.

i just put a new fuel pump no a 1999 chevy 2500 cargo van,it still will not startit has a 350 in it,can someone help me

So I will assume you have spark, seeing how your questioning whether it's carburetor or fuel pump. With a mechanical fuel pump, the easiest way to check is to disconnect fuel line at carburetor, and aim it in to a pop bottle, or similar container. Remove connector at distributor so no spark.
Crank engine over and see if fuel runs in to bottle, or container. If good flow, pump is o.k.
The proper way would be to hook a vacuum gauge up to inlet of fuel pump and crank engine and note vacuum.

Pull a couple of the sp. plugs out and see if there is fuel on them. If not pull the o2 sensor out of the exhaust and see if it starts. It will run rough but should start and run. If it does start you have a plugged catalytic converter or muffler and it is putting back pressure on the engine and not allowing the fuel into the cylinders.

not sure if this helps but have a read on this

page.http://www.2carpros.com/forum/1979-chevy-van-1979-chevy-van-nuetral-safety-switch-locatio-vt135072.html

Check to see if the fuel pump is kicking in,
when you turn the key on without starting the van you should hear it kick on for about 2 seconds,

It could be...
A clogged fuel filter...
Blown fuse for the pump..or bad pump relay..
No gas
Bad fuel pump