1987 Chevy S-10 trouble starting vehicle after it warms up

I have a 1987 Chevy S-10 with 160k miles on the 2.8 engine. I'm having a problem with it as follows:
It starts and runs o.K, but when the engine has warmed up and I try to restart it after a few miinutes, it will not crank. I replaced the fuel filter, but that didn't solve the problem. When I was changing it, I noted that it was getting fuel to the filter and had plenty between the filter and throttle body. I can hear the fuel pump working as well. Can you advise what the problem might be? Thanks, Keith