Most of us at one time or another will clean our old games with a cue tip and rubbing alcohol.  One problem is your average rubbing alcohol has 30% water in it.  Which water will corrode the connectors, very quickly.  So what should you do:

If you do have a 70% rubbing alcohol solution, pour about 1/2 cup in a sauce pot, and bring to a boil.  Be careful not to boil the solution to long, as the alcohol will catch on fire.  (Stand Back)  When bringing the Rubbing Alcohol to a boil, the water will evaporate, and you'll have a concentrated solution to clean your games.  Make sure to let it cool down.

You could also look to find a higher rubbing alcohol solution, but 100% is hard to find.

Now you're ready to clean:

• You'll need a small square sponge section, a lint free rag, and a pair of needle nose pliers.  What you need to do, is rub both sides of your game connectors for a bout 10 seconds each side.
  
• Do this by dippping the sponge in the alcohol solution.  Then gently press and rub each side of the game on the connectors for about 10seconds each side.  ( I use pliers to hold the sponge.) 
  
• Then wipe the connectors dry with a lint free rag.  You can use cue tips, just make sure you don't leave any cotton on the connectors..
• Just be careful not to put too much in side the system as, you could damage the pin connector or the circuit board.

Your games should now be clean.  The best way to store your games is in a dry dark place.  Preferably in a protective case or a bag.

The Ultimate Tip:

Use 180 or 240 Fine Grit Sand paper, and rub it in an up and down motion on the connectors.  This works great on your games, and pin connectors.  I've turned none working games, into perfect working games, with just using a little sandpaper.

• All you need to do is, cut a small square of sand paper, and your ready to go.  As you do this the sandpaper will turn black, which is from the carbon you are removing.

• I generally will keep a can of Dust off around, (Pressurized air in a Can)  This is great for preventative maintenance for your games and systems.

The last option I have used:

• A pencil Eraser, this works great as well.

How to fix your old Nintendo:

If your like me you've probably hit that old Nintendo, played it upside down, shooki it until your arm hurts.  Just to get your favorite game to work.  Easy solution

• Buy a New 72 pin connector on eBay, they cost between $1 to $5.  Be carefully some eBayers will jack up the prices on shipping!

Then install the new pin connector, and your system will work like new, I promise.