Re: Are kill cord all the same or they are engine brand dependant?
I assume you mean the clip and the fitting it clips to. There are several varieties, starting with each motor's brand, but I wouldn't be surprised to see some mismatched through the years.
So if your engine did not come with the cord and clip, but has the fitting, you do have to match it and best odds are start with Yamaha. However, I found that the replacement cord that comes with about 5 different clips costs about the same as a brand-specific, so I got that to have spares for my other motors and to help out those who lost/misplaced/forgot theirs (as has happened once at the "marina" and once at the hunt club).
One reason it's good to keep a spare on board is if you fall overboard with it attached, your crew will need a second one to start the motor and come get you. In windy or current conditions, it could be dangerous to leave the crew in a disabled boat. A few motors will restart if the kill switch is yanked out; test yours.