My 12b sound like a lawn mower
 

I have a 12b n just like to subject state.... I was race wen it happen....wat could of cause it n will I have to rebuild

You mean a 12A.

Perform a compression test: http://www.aaroncake.net/rx-7/blown.htm

Yowzer, I had to read that three times to understand what you were saying. . .

I'll be honest here. . . . I just kind-of think rotaries sound like giant lawn mowers. It was certainly my first impression when I bought my GSL

At least making the ATTEMPT to write coherently will allow others to help you. I agree with the guy above me....rotaries can kinda sound like weed whackers when working normally.