Can you please tell me if this is correct….Boyer Mk 4
Degree timing disc mounted on the rotor, TDC found using DTI in the plug hole, Rotate the engine forward by almost one revolution until 28 degrees BTDC is found then line up the white dot via the spy hole in the stator plate…ATB Chris
Dti will not get an accurate TDC, too little movement plus rocking of piston. You need a piston stop in plug hole, turn both ways and split the difference.
Thanks….will do….how about the rest of the question?
As John says …
I'd add that once you have accurately determined 28º btdc it's a good idea to make a piston stop (using the time honoured method of excavating the centre from a dead spark plug and tapping it for a suitable screw) that will indeed stop the piston at that position.
Carried in your toolkit it will be shorten time at the roadside if you strike trouble away from the workshop.
You need to make sure you are 28 degrees BTDC on the "compression stroke" of the RH cylinder when you align the dot on the rotor with the hole in the stator.
One other thing on the Boyer pick up plate you have two holes one clockwise and one anticlockwise for the timing
You can do the same thing with Dti.
Set the DTi as near as you can to top dead then zero it and the Deg disc. Rotate the crank to say 10deg BTDC and note the reading on the DTi.
Rotate the crank in the other direction to just past 10deg ATDC then rotate it back to10Deg ATDC and note the DTi reading. Split the difference reset the DTi and the disc to zero, recheck and that's top dead.
Its much the same method as a dead stop perhaps a bit more fiddley.