Question : starting system help bench tests good

[deimmortales]

i bench tested my starter its good works well solenoid good too. reinstalled it. and it wont spin the solenoid just clicks. any ideas why when i install it it would just click?
update: I bypassed the starting system and just wired signal to b+ and the motor power to b+. then neg to ground the car to a known good battery. solenoid did the same thing except it clicked once instead of rapidly clicking. but the motor didn't spin when i touched the jumper to the battery.
still not cranking. ideas anyone?