Here is a video showing how to replace the gas piston in your MAK 90.
[ame]http://www.youtube.com/watch?v=S0hnyTzE2cw[/ame]
It is not as hard as it looks if you have access to a drill press you could do it your self.
[ame]http://www.youtube.com/watch?v=S0hnyTzE2cw[/ame]
It is not as hard as it looks if you have access to a drill press you could do it your self.