Hi I have a Mercruiser 3.0L in my 2002 Bayliner that I am trying to
check the timing on. The first time I tested it with my timing light
it said it was 12 degrees BTDC. Next I decided to read the shop
manual

and it said I had to join to white wires comming off of the
distributer and to disconnect the Shift interrupt switch. I did that
and tried checking the timing again and it was still 12 degrees
BTDC???
What did I do wrong? I was expecting the reading to change when the
two white wires are connected.
Oh, my idle runs at 900RPM and the manual says my timing should be 2
degrees ATDC.