wcb98:
it was rated at 3v, but I didn't know what it's maximum voltage rating capacity was,
That is not an unreasonable speculation but the critical question is what current it can take rather than what voltage.
You must ensure that you don't operate with a voltage that forces too much current through the motor. As @PeterH has stated the stall current will be very much higher with 9v rather than 3v. Safely increasing the voltage above 3v might be possible but increasing by 3 times seems excessive.
Also, if you are using a small 9v PP3 battery it won't be able to supply a lot of current. A bigger 9v battery or a 9v mains adapter might cause damage to the motor where the battery would not.
I believe there is a considerable voltage drop in the L293 and if so a 3v battery won't provide 3v to the motor. You may need a 4.5v power supply.
...R