Originally Posted by
Truckracer
So far, no one has mentioned the differences in ignitions. Most newer ignitions will retard the spark during a brisk flip of the prop and this will allow a fairly easy and safe hand start. But there are still ignitions out there that don't retard (are fixed timing) and will bite you if given a chance. What ignition are you using on that older Tartan and does it retard during startup?
It is an old CH ignition with no ECU-type timing or electronic timing retard. The engine does have a mechanical linkage ignition advance from the throttle to the hall effect sensor disk. (Advancing the throttle advances the timing.) Both cylinders fire at the same time by the way so it has considerable compression going over TDC.
Appreciate all the advice so far. The short blips I got yesterday with no fuel tank connected seem very consistent so will try to run it tomorrow.