Br800 magnum

[Mad_mat222]

Greetings,
this machine won’t run. Plug is good and I replaced the coil which I now believe wasn’t the issue. Still could be wrong but the chances of a dud coil arriving is pretty slim. What am I missing. I disconnected the kill switch wire from the coil and still no spark. Coil is gapped correctly. I was cranking it over using a drill so plenty of revs.

im struggling.
new coil + good plug+ attached to machine and earthed correctly = spark

 

[bertsmobile1]

Did you install the new coil right way round ?
They are polarity sensitive .
Did you buy an engine branded magneto, aftermarket one from a genuine mower parts supplier or a defective one from Scammazon or Evilpay ?

 

[Mad_mat222]

Did you install the new coil right way round ?
They are polarity sensitive .
Did you buy an engine branded magneto, aftermarket one from a genuine mower parts supplier or a defective one from Scammazon or Evilpay ?

Genuine $200 stihl coil. There is really only one way it can be fitted due to coil lead routing. So yes.

 

[bertsmobile1]

At cranking speeds the spark on some of these is very feint as they idle near 2000 rpm & run around 10,000 rpm.
The spark that a magneto generates is proportional to the speed that the magnets pass the coil.
So the faster the bigger
The other thing is the air gap
A closer air gap will generate more AMPS as you get better coil saturation.
OTOH it will also be slightly advanced

 

[StarTech]

Also those CMR plugs can be pretty flakey at times. You said good plug. So I assume you mean a known good plug from a working engine.