No spark

Bob Hedgecutter

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Sorry, cannot help you there- I never use a multi meter to test coils or spark.
I rely solely on a bright brilliant spark from the plug outside the cylinder and grounded to it- if it don't do that- something is wrong.
First places I check are faults in wiring from coil to kill switch and faulty switches- then suspect the coil (although a cold coil will usually fire, run the saw and then die once warm) and lastly the flywheel.
 

Cskyline

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Thank you for the reply . I have changed the coil out with China made knock-offs even ordered one from Germany looks China made as well. No spark on any of them really grasping for straws on this one
 

MadKaw

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That wire resistance seems awfully high. I don't know about chainsaws in particular, but in other engines, typically a spark plug wire has about 5kΩ/ft., and a non-resistance wire is ~50Ω/ft., so unless that wire is 2' long, either there is something I don't understand about the system in that chainsaw, or the wire (or boot) is defective.
 

Cskyline

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Yes it a new wire from a stihl dealer 6mm I think
I don’t like it . I did get the saw to spark . I removed flywheel coil and wire from another sach dolmar and installed on the 133 plus an Oregon 33-053 ignition module . I will put some fuel in tomorrow to see if it will hit . I appreciate all the suggestion and help from everyone I am no chainsaw mechanic just got a little uncommon sense .
 

Cskyline

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That wire resistance seems awfully high. I don't know about chainsaws in particular, but in other engines, typically a spark plug wire has about 5kΩ/ft., and a non-resistance wire is ~50Ω/ft., so unless that wire is 2' long, either there is something I don't understand about the system in that chainsaw, or the wire (or boot) is defective.
8” wire had 0.4 ohms . Secondary of coil 9.3k Ohms. Primary of coil was 1.5 ohms
 

MadKaw

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Clutching at straws ... how do you know there is no fire? Not doubting, but maybe there is a clue in your testing method.
Using a spark tester?
As I recall, you've tested the magnets are at least strong enough to attract a screwdriver...
Couldn't be a dead plug, could it?
I reread your post #7. That makes it sound like the ignition module is bad. That's all I've got.
 

Cskyline

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Well the plug worked in a different saw and is new. I got it to fire with throwing parts at it. So I will be trading those parts back one by one to see which part will effect the spark again.
 
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