1990 Sierra wont start

turn the key and i have juice but engine wont turn over new battery starter alternator is good. After new starter was put on it ran fine i started and shut it down 5 or 6 times few hours later went to start and same problem wouldent turn over

Welcome to AF, make sure all the battery connections are clean and tight, check for 12v at starter solenoid ign wire., when someone holds the key in the crank position, post back results. Stick or auto also.