Identifying problems with Cartridge games/systems

[Lamegamer]

I was wondering if someone could help establishing what is the general main cause of problems between cartridge games and the systems. Someone here is selling a large box of games with a Megadrive II for a very reasonable price. When I asked the condition of the system they said it works well but you have to blow on the cartridges a lot and it got me thinking what actually causes this issue and is there an easy method to clean what is causing thsi from general household items?

To be honest the price is worth it and just to get rid of the Megadrive if it dosent work but if this problems is caused more by the games itself it might not be worth it.

[bartre]

in general, it's caused by 2 things:
dirty connections and bent pins

both are typically very easy to fix.
dirty connections - just get some rubbing alcohol or something and a qtip and scrub em.
bent pins - use an eyeglass screwdriver, or something similar, and bend the pins back closer together - but BE CAREFUL, don't break the pins.

[retro junkie]

I use an "electro wash" type stuff used in cleaning PC boards and a scotch pad. I take my cart apart and clean the pins. I really don't have to do the blowing after this proceedure. Seems to last a long time.

[bartre]

ooh, one thing i forgot.
if you go to the trouble of opening the cart, but don't have the computer cleaning stuff, try rubbing the contacts with a pencil eraser.

[bacteria]

Indeed, a pencil eraser works fine. I did that the other day with a ColecoVision game - inserted it and it said "ensure you turn off your console before inserting a new cartridge" (in other words, didn't know there was a game present), opened up the cartridge, used a pencil eraser on both sides of the contact, then game worked fine.