Went to change cartridges and cannot remove the old. Went to Google and Utube and tried the stuff recommended in the various videos without success. Probably have to dismantle the gun, which is more of a task than you think because you all sound like you are very handy and I am all thumbs. Before turning my pistol into a pile of parts I wanted to try to put some Kroil oil in there and let it sit a while. Is that going to cause me additional problems?