1938 English Fordson Magneto timing

Rotate the crankshaft by means of the starting handle till No. 1 cylinder is at firing point. This is when the piston is at top dead centre with both valves closed. The easiest way to find this is to remove the valve cover (the long cover under the manifold) and No. 1 spark plug, insert a piece of wire down the spark plug hole on to the top of the piston. (make sure that is at least 8" long otherwise you might lose it.) Rotate the crankshaft until both valve springs are fully extended showing that both valves (on No. 1) are shut, and the upward movement of the wire stops showing that the piston is at top dead centre.
Remove the distributor cover from the magneto, and rotate the magneto impulse coupling anti-clockwise until the rotor arm is pointing towards that segment of the distributor numbered 1 and to which the H.T. lead from No. 1 spark plug should be connected. Turn the armeture so that the points are just about to open with the rotor arm in the above position.
The lugs on the magneto coupling will be approximately horisontal and the lugs on the driving shaft will be vertical.
Install the fibre coupling and slide the magnito forward on its bracket, bolt on reconnect wires etc.

You can also download an E27N manual from>Link

Regards, Frank.