Hey George, I think the V-shaped inserts tend to get a lot of wear around them, and I think I may have heard they may be prone to cracking moreso than most inserts with too much heat under them. Good luck with the game!

You will have more luck finding an F-14 Tomcat. There are a great game for there age. Most parts that wear out are available online. Watch for battery acid damage on the main board, make sure all solenoids and flashers are working and check the displays in the test mode. Listen for all the sounds when you play it. Good luck with with your purchase.

Im not sure if there is a you tube video on this you should look and see. Anyway you open the coin door and there is a set of three switches. Off the top of my head I think the middle switch is the one that can lock in the down position.
Lock that one down then press the left one once then unlock the middle one, then press the left one to advance to each test. Or something like that. If my wife wasn't yelling at me to get ready for thanks giving at my mother in laws house I would go to my machine and check for sure. I will have to check later today. Sorry.

To add to what Collin said, not just wear but the Inserts (which there are many) pop up and out, so being comfortable with leveling inserts is a must for this game. Its how I learned, as the game I bought, almost half the inserts where starting to rise making the game unplayable till I fixed it.

I made it back from the mother in laws and haven't died yet. Anyway to do testing on system 11 machines you turn it on and open the coin door, lock the middle bottom down. Press the right button (advance button) once, then unlock the middle button and your in scrolling display test. If you lock the middle button down it will stop scrolling. If you press the right button if will advance to the next test (solenoid, lamps ,sound). By doing each test you can tell if any part of the game is not working. It might seem confusing at first but after a few minutes it become second nature.

Here is a link to the manual, it explains how to access the test mode, how to run them, and what each of them do. It will be a good idea to print out that section or become familiar with it before you go.

http://mirror2.ipdb.org/files/804/Williams_1987_F_14_Tomcat_Full_Manual.pdf

Common issues include:
Raised inserts
worn playfield
light beacons on top that are missing (expensive to replace) or not rotating (cheap part easy to replace)
Take the glass off and start a game. make sure all of the switches work and all the locks work. Start a multiball, see if the game resets during multiball, it can be a common problem.

None of the issues above should prevent you from buying one, but if they arise you can use them to lower the price.

They lift as well.

This ^

Common problem, also the white beacon tends to have yellowed on most over time.

Excellent advice for any pin purchase!

Also a common wear spot is under the spinner.

All in all a great fast paced game.