(quoted from post at 21:17:03 03/09/18) have you got a link to a good inline spark tester like the one you describe?
thanks
Google "spark tester light" they are around $10 most all parts stores have them.
Google "adjustable spark tester" another $10
Mark your flywheel were you want the total to be install your light and adjust the dist. to that mark at what the total advance should be at the recommended RPM.
Sometimes spark and fuel issues mimic there self it takes a trained ear to tell the difference and then it not 100% reliable.
What does a light tell you (the one you hook in series with a plug wire)
What we don’t know and what it will not tell you is spark health (KV) If you have a good runner with intermittent issues you learn to judge spark health by the color of the light You will have to be the judge.
On a no start it can be used to see the event now what has that told you.
The event is happing the points and coil are functioning on a EI set up the module is trigging the coil. That’s about it but good info to have handy.
What we don’t know and need to know is spark health I will let you fill that one in you will need an adjustable spark tester for that info lets get back to a light as a helpful tool.
Let say we have a engine that starts runs well but sputters acts like a fuel issue it may clear up it may not it may run good one day the next it won’t. Install the light spark checker start the engine and monitor the light when the event happens if the light flashes a normal spark even as its sputtering are shutting down spark is not you problem. If the light shows a weaker light, are the light is strong and then weak are missing flashes I go straight for an ignition problem.
The number one issue I see is points new are old on an intermittent sputter acts like fuel issue they will light off a 12V test light hooked between the points and coil perfect it will fire a KV tester don’t take that to that bank spark is OK it will bite you. The prof on a runner is to back it up with a inline light spark checker and monitor the flash when the event happens as I have mentioned. I can do it with an adjustable KV tester only because I have ton’s of experience with it.
If you verified good spark health with a spark checker THEN a spark checker light tool may come in handy to catch an intermittent issue. The tools needed are a adjustable spark tester and a in line spark tester with a light.
A adjustable spark checker is to check spark health an in line is not. A in line with a light is to capture the event you will use your scene of site to evaluate the event.