Hi. I'm having a problem getting a spark from the chainsaw. I've replaced the coil with a new genuine, replaced flywheel with the same, set the coil/flywheel gap but still nothing. I've even disconnected all wiring and connected up my spark tester. No spark. The secondary resistance of the coil is 2000 ohms. Can anyone help?

Stihls are notorious for weak spark.
 
Just for S & G's, pull the spark plug out and remove the pull starter cover.
See if you can set up your drill to take a 1/2" / 13mm socket.
 
Spin, with the drill-(NOT AN IMPACT GUN) the engine (crankshaft) in the normal rotation but fast.
Have the plug attached to the spark plug wire grounded to the cylinder and check for spark.
 
I've seen very little to no spark at slow (pull starting speed) but spark at a much higher spinning speed.
And with that, no visible spark, it'd fire off...  
 
Also, try another spark plug gapped at no more than .020"...
 
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Many thanks for that. I have spun the flywheel with my drill and with the spark tester connected but could see nothing. I'll try another plug at .020" at a faster speed and I'll let you know!! BTW, do you have any idea what the primary and secondary resistances should be for these coils? I contacted Stihl ' Technical Advice ' and they told me that Stihl don't issue any such data and actually were NO help whatsoever. Thanks, Danny

Stihl is super tight lipped about everything.  I usually go to a UK site to bring up parts diagrams...
 
In any event, I don't know the spec's.  With a brand new coil, new flywheel, obviously it should have spark.   I'd make sure the end of the plug wire, with the steel/pointy plug attachment is fully pushed into the wire.
 
You can try the old coil again as well.  Just cause it's new, doesn't mean it's good...
 
I have, on rare occasions, had Stihls not make spark, even with new coil, known good coil, etc..
My commercial tree guy (customer), with his many machines, ends up with a parts machine... :(  
 
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