Vintage Alvis Maintenance
MAGNETO TIMING - Firing Point - 3
The objective is to set the Magneto contact breaker points to open when the Distributor Rotor is pointing at the #1 Distributor segment which will then create a spark in Number 1 cylinder.
• To check the timing of the Magneto you will need to take off the Distributor cap which is usually held in place by two clips, two screws or two studs with nuts, depending upon the model and make of your magneto.
• Looking from the back of the Magneto, with the flywheel rotating as though it were running, the Distributor rotor will rotate clockwise.
• Mark the Magneto coupling with paint, or whatever, just when the points start to open
• The firing order is 1 - 2 - 4 - 3. I usually label the spark plug cables from the 7 o’clock position for #1, 10 o’clock for #2 cable, 1 o’clock for #4 and 4 o’clock for #3.
• Assuming that you have checked the points for pitting and that there is a 12 thousandths of an Inch gap (TVAM Chapter 11, 224) then we are ready to connect the Magneto to the Engine via the Dynamo drive and the Simms coupling. To adjust the gap please click here.
This website contains my personal Maintenance schedule based on the late Micky Radford's "The Vintage Alvis Manual" and is supplemented by Lubrication charts from the Alvis TJ 12/50 Instruction Book. These project notes are based purely on my own experience and are not intended as advice or guidance to the reader.