My Question is That my Lawnmower will crank but when you release the clutch/brake it dies! Why would it do this?

Check your safety switch

Check under your seeat. There is a "dead man's switch" that cuts the mower off when you get off and the brake/clutch is not engaged. On possible answer is that the switch is slightly disconected, causing a short. Another possibility is that the seat is not coming down all the way and allowing the safety to disengage. If the weight factor on your seat is adjustable, try to put it at a lower weight. If the springs are distorted, try to replace them.

Sounds like the safety switch under the seat is bad, or may not being contacted by the tang that is pointing downward from the bottom of the seat.