I am planning on taking my lower unit apart on my '65 Mercury 650 this winter to reseal it. I have a Glenn's service manual and a Clymers manual for this and they both explain gear backlash and what it is supposed to be, but do not exactly explain how to measure it (I was guessing using a dial indicator). I would like to do this right the first time if at at all possible and I don't think this motor is worth paying someone big money to do this. Any help from anyone who is familiar with doing this would be appreciated.
