I am attempting to make my own valve adjustment tool, using a socket, screwdriver, and wrench. In making my tool, I would have to drill the inside of the socket a little, for the screw driver to fit right. Then machine the outside of the socket to fit the wrench, so I want to make sure I'm using the correct size socket. I thought the locknut was 10mm, but the Helm manual says 9 x 0.75mm. Which is it? Thanks

 

I guess it might depend on the motor... Most I have seen are 10mm

 

i know mines 10mm

 

J30 (03V6). I hope it's 10mm, cause I already drilled the inside of the socket.

 

OK guys. This is what I created. I drilled the inside of the 10mm socket, so that the screwdriver would fit through it, without much play. Then filed opposite sides of the socket, so that the 14mm wrench would fit tightly on the top of the socket. I think it will work great. Any opinions?