Hi Jack,
Actually it was all okay. I just had to move the magneto as far to one side as possible to compensate for the correct cylinder spacing. Even though Tecumseh reversed the position of the valves and ports, they still operate exactly the same way as before, which is only to be expected really. The firing of the contact points in open position is also perfectly correct. As I turn the engine over I can see it is doing everything in exactly the order that it should.
Now to complicate things a bit further, I noticed that the cam lobe and points off my old Kirby-Lauson were looking a bit dodgy. But I installed them so I could get the timing correct. Then I removed the wire off the points and totally removed the condenser. I fitted a Stens electronic ignition system instead. It works exactly the same way, firing at the critical time, so timing is unaffected. For some reason I notice the spark does not seem to be quite as strong as with the old points and condenser, but still there is a good spark there nevertheless. I guess only time will tell if the spark strength is up to the task.
I was talking to PaulC about these Kirby ignition systems and he mentioned that he has only ever seen two brands of ignition system used on the old Kirby-Lausons, and these are Phelon and Wico. In both cases the points fire when in the open position.
