Volvo: 1990 Volvo GLE Station Wagon Electric Prob, old battery, extra power

Question
So my Volvo sometimes does not start.  It appears to be electric in nature, because when it does not start it always will after a jump.  Then it is ok.  The battery is new and it was doing it with my old battery too.  I tested the voltage on the battery and it was a little bit over 12 volts.  When the car was running it was a little over 14 volts.  When the car is running and I disconnect the battery it continues running fine.  So it does not seem to be the alternator or battery I guess.  The problem seems to come and go randomly.  Any ideas?

Answer
William,
So what you told me is that the starter is acting up. It needs extra power to engage. You also stated that the chargimg system is working properly. Now is the starter worn out is is there not enough power being sent to it? With just the cars battery hooked up see how much voltage is at the small wire at the starter. You need at least 10.5 volts. If it is lower then you have resistance in the wire system and or the neutral safty switch. The large wire should always have 12 volts. Be sure that the grounds are all good and tight.