18A Zenith downdraught eratic running

[Sunnysoutheast]

Originally Posted by Rustinmotion

To run on you need a source of ignition and as the coil is off something is hot enough to ignite fuel and keep the engine running, usual suspect for this is a carbon build up that glows red hot
Can you do a plug cut, find somewhere safe to drive the car under load and switch the ignition off and dip the clutch then safely pull the car to a stop, take the plugs out and check the colour, this will tell you how it’s running under load rather than at idle
Can you blow out the pipe between tank and pump, that might be partially blocked
I’d still verify the float setting it’s not unusual for it to be wrong on a new carb

I shall check the plugs, rotor arm and re-test.
I could also try the "plug cut" you explain so well.
I did blow clean the front to back pipe before the new tank was installed.
And re-check the float.
Cheers.
Dave

Got family stuff this afternoon so might have to wait till next weekend.