I have a metal coupler about 3" in diameter with a shaft through it. The coupler is at the end of the shaft of a motor, and is about 15 pounds. The motor is parallel to the bench it is on. There are two Allen screws that are separated by 135 degrees screwed into the coupler. I can not get either of them out. I'm using a 1/8th inch Allen wrench and do not want to break it.
I tried using penetration oil to dislodge the screws, but to know avail. Any suggestions?