1994 Chevy S-10 S-10 truck wont stay running

1994 s-10 pickup truck that will only start for a few seconds then die. But if I keep doing this for 40 or 50 times it will then stay running and its all fine. But I keep having to do this when I leave it sit for a lengthy time.24hrs.I put a new fuel filter and 2 new fuel lines on but still same result.I can here fuel pump coming on when starting. Seems like gasoline has to build up before it stays running. Why does my truck do this