I am replacing my starter on a 89 Chevy c1500 4.3 v6. I took old one off and put new one on, old starter had 2 wires new starter has 3 places to put wires, the main positive cable and 2 small ones labeled R and S, I hooked up the starter and fired engine up with nothing,engine didn't start what could be the issue??

 

Which terminal did you put the small wire on R or S? It should be on the S. If it is on the S then check to see that you are getting 12 volts at the small wire when the key switch is at the start position!