My reo mini spring collapsed when i put bottom coil phoenix on it, dont ask why... Impatient wife... Anyway i was having issues with 3 different BC so i loooked at the bottom of the threading. The negative pole was fine, but there was a wire sticking out of the bottom from the middle and stuck to the outside thread with what looked like a spot weld. Just double chck youre bc befire using incase you have the same issue as me.