Is there a way using multimeter to determine whether or not ignition coil is working? And to determine if the coil is producing the energy to start the mower. Craftsman 917.986450 26hp 54” with Kohler KT 745-3012?
You can test the secondary resistance ( coil to plug cap ) with an Ω meter however few manuals publish this data because the coil can not be repaired.
To clarify, a coil is just a transformer with 2 or more sets of windings that produce a different output voltage to the input voltage
as such they have specific primary & secondary resistances .
IF your mower has points or an external trigger module then it can be tested
Back in the 50's Atom invented the Hall Effect trigger circuit that could be used to replace the points on flywheel magnetos
In the mid 60's they marketed it in colour coded enclosures with different amounts of delay to suit different engines as a "Computerised Points Eliminator "
The chip was worth 50¢ ( Aus ) back then and is worth about 5¢ now
Husqvarna , Victa , OMG & eventually Stihl & Honda all adopted them while others waited the 30 years for the patient to expire because they refused to pay the 10¢ per unit royalty despite it saving $ 5.00 per engine.
Once it was out of patient , every small engine maker fitted them externally to the coil
Then some smarty worked out that they could put the chip inside the rosin surrounding the primary windings of a $ 5.00 coil so turn the $ 5.00 coil + the 10¢ chip into a $ 50.00 module
This simplified the assembly, allowed an extra $ 45 of profit and because inside the potting it could not dissipate eat as well, shorten the working life thus require regular replacement ( laughing all the the way to the bank at your expense )
Now the common Hall Effect chip uses transistors so it means that Ω meter readings were either impossible or totally unreliable .
Some can be tested most can not but even if they can be tested they can not be repaired so it has become works / don't work situation.
I have a box full of old Victa trigger units that are 20 to 50 years old and they all work perfectly where as the ones embedded into the coil have all failed
Henry Ford would have been rightly proud .
