Subject: Starter Motor Problems
Question:

'92 Mitsubishi Spacewagon 2.0 GLXi Manual.
I have had problems for several months with starting difficulties (probably worn ring gear), but have managed through a combination of patience and bump starts to keep the car in use. The starter motor has now begun to stick (fail to disengage). I obtained a replacement used motor, but after removing my original starter motor found the replacement is not correct. As I have the original motor removed from the car, is there anything I can do to prevent the "failure to disengage" problem before putting it back to use until I can source a correct replacement?
Answer: Richard,
The solenoid could be stuck. When the solenoid goes, many times the starter won't even turn over, or never stop turning over. Worn gears are another possibility. There is not too much you can do to prevent the 'failure to disengage' other than rebuilding the starter. And in fact, the replacement motor you get will most likely be a rebuilt motor.

If you can wait, I wouldn't bother trying to get your old starter to work before your new one arrives. That will just add more frustration. If you do install the old starter again, and it will not disengage, you could always try the old-fashion trick and tap it with a hammer.
Good luck!