why is my starter not disengaging after the vehicle is running?

i have a 1979 jeep cj5 on 38's with a 360 v8. Yesterday i was driving to
school and the jeep acted like it was running out of gas, sputtering very
bad. I pulled in the gas station and it only took two dollars in gas and it was
full again. Then i went to crank it up and it wouldn't start. So i went and
bought a new starter and solenoid, I even tested the battery and it was fine.
This morning i went to try and jump it off and the starter kept running after
the jeep was cut on. The started never disengaged from my fly wheel. Took
the starter off the make sure it wasn't grinned up and it was okay. Placed
the starter back on and the jeep will not crank up the starter just makes a
terrible noise. do you think that the jeep jumped time and the timing is off?