ok so i've swapped over my old pierburg carb, cleaned all the spark plugs up and gave it a go. It ran! For about 10-15 seconds and then cut out like it was doing with the brosol carb.
I've tested all the resistances, replaced rotor arm and cap
King lead 2kohms, exactly at spec
HT leads 6kohms, exactly at spec
Rotor arm 1kohm, exactly at spec
Battery voltage 12.8
Battery cranking 11.7
Ignition coil voltage 12.4
Coil cranking 10.3
Coil primary resistance 0.8 should be between 0.52 & 0.76
Coil secondary resistance 4kohms should be between 2.4k & 3.5k ohms
According to brickwerks post
https://www.brickwerks.co.uk/brickwerks ... ion-coils/
So my coil is out of spec
I've swapped over an old ignition amp and dizzy and also got the same results, consistent spark at the plugs when ground against engine and it runs until the spark plugs choke up with too much fuel which as Ajsimmo said could be the Brosol carb but i don't think my pierburg would have the same issue if it was that.
So i've got fuel (but not too much going in)
I've got enough air
I've got some spark, but yellow/orange colour whenm supposedly should be blue, so i really feel it might be the coil. I've got a new one coming down hopefully by tomorrow so will be good to see then. If that doesn't work i've got no clue where to go from here though.
Has anyone tried to ground their spark plug against the engine to observe the colour? Would be good to see what other people get trying that.