Since I have it apart..should I replace the coil?

#1
I have a couple snowblower engines in various degree of being apart...detailing, painting exhaust and carb changes blower / recoil swaps... should I replace the coil just because I'm there? Are the cheapo chinacumsehs good enough? [$11]
 

Mr. Pink

Well-Known Member
#6
This week I learned that there has to be continuity between the armature of the coil and the engine block in order to get spark.

Three weeks ago, the primer bulb disintegrated on my 21 year old Toro snowthower with a two cycle Briggs in it.
After 47 pulls of the starter cord the engine started and I got the driveway cleared.

Of course, I waited until this week, the morning after an 11” snowfall to replace the bulb.
That repair went smoothly, but the engine would not start, no spark.

I’ve always thought the same thing creia said “coils on the Briggs and Tecumsehs engines vary rarely ever go badI” so I reluctantly purchased an aftermarket coil on Amazon for $14, followed Taryl’s innstructions
and installed the new coil.

Still no spark.

I installed a new plug, still no spark.

I then found a video by The Mower Medic

I took an ohm meter, measured the continuity between the coil armature and the cylinder head and saw infinite resistance.
I then took some sandpaper to the to the back of the armature of the original coil and to the mounting boss on the cylinder and reinstalled the coil. Now the measured resistance between the armature and cylinder head is less than one ohm and I have spark!

I then sandpapered the lacquer off the area around the bolt holes of the new coil and was now able to get spark with that coil.

I’m thinking this is probably what joshua.c. meant when he says “Clean all the rust off the coil and magnet “.
 

joshua. c.

Well-Known Member
#7
no I meant paint it. Maybe you need the contact point with the block to be clean of paint but I've painted all my coils and magnets after cleaning the rust off of them with no issues. (10+ motors) I even left an engine in the yard with no cover on it for 3 years strait without a spark issue. clean coil and magnet = good spark, paint them after = spark forever.
 
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