1969 Merc 100SS Timing

[Jeffon2ndMate]

I am trying to find a way to time this motor (Ser#2685511) with a standard (Matco) inductive timing light (2 stroke capable)as I can't find an original Merc (C-91-35507A1) timing light.It is running good, but the timing belt is rough and I want to change it. I have "Thunderbolt Breakerless" ingition, and when I hook the light to #1, the reading is WAY OFF. Infact, it doesn't read close to the marks no matter what cylinder I hook my pick-up to. I don't want to crack a bolt until I either get a light, or come up with an accurate method useing my inductive light. Can anyone help? Thanks in advance..........Jeff

 

[Kenny Bush]

Re: 1969 Merc 100SS Timing

Try a different timing light. You won't be able to use timing marks for cylinders 2 thru 6. You should have all the instructions and specs in your manual. You will have an idle pickup time and a max advance time. If you move the #1 piston to TDC, The timing pointer should on the "TDC Mark" on the flywheel. If you look at the top of the distributor pulley, there is an arrow that should be pointing at the TDC mark on the flywheel. Changing the belt is fairly easy, and you will need a small 5/16" wrench to take to distributor pulley cover off.