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1972 Johnson 9.5 No spark on either plug.

K

KyBullet

Member
Not familiar with the older motors, but i would guess magneto? Problem is i can not for the life of me get the flywheel off. Any tips? I have tried a puller, been soaking it in wd40 will no avail. Thanks
 
Those flywheels come off easy with the correct puller.----Lube is not needed.----Heat is not needed.-----Yoa are using a hefty puller and 3 bolts I hope.
 
Yes using a 3 bolt puller and nothing lol I do have 1 bolt that's different I will try to figure out what size they are and get 3 new ones.
 
KyBullet said:
Yes using a 3 bolt puller and nothing lol I do have 1 bolt that's different I will try to figure out what size they are and get 3 new ones.
Click to expand...
What do you mean by one is different? There is only one size that will fit the threads in the flywheel. If they are the same length, & you’ve turned them in the same # of threads, they should be all pulling the same.
If one is longer, you could shim it with a nut or a few washers.
if your puller is not the factory one, make sure the flat side of the 3 armed plate is facing up. Mine has one side sort of curved, if that is “UP”, it tends to force the bolts outwards vs straight up.
Put some oil or grease on the threads of the Center bolt so your losing less pull to friction. I once used a rubber strap wrench to hold the flywheel & be able to turn the Center bolt more.
With some decent force on that Center bolt, & a good whack…it has to come off.
post a photo of your setup.
 
Wires from coils going to correct set of points ?----Cam upside down?----Coils properly adjusted ?----You had the magplate off to install new wires into the coils ?--Easy magneto to maintain.-----Post a few pictures of your magneto.
 
Continuity from coil to plug is not a guarantee of a good wire. It does show that at least one strand of the wire is continuous.
i had a 6hp that showed continuity, however it wouldn’t spark. Racer got me a new wire, & it sparked. After cutting the old wire open, I found internal corrosion & a bunch of broken strands.
I also found a bad condenser, though it’s seems odd that both are bad. They are cheap, get one new one…if that doesn’t show spark, it’s unlikely they both were bad.
 
easy way to test- 1st before you put flywheel back on check that the shoulders of the coil are lined up vertically EVEN with the outside edge of the mounts- if back too far will not give you a good spark.All good there put on flywheel and nut. Remove BOTH plugs from engine but plug in plugs to boots.Put engine in neutral-turn flywheel by hand and should see prop stop turning.take a small drill 12v will do and put on socket same size as flywheel nut.Threaded end of plugs need to touch engine block to ground to produce spark (can just sit against and can even check 1 at a time- DO NOT HOLD ! put drill on nut-engine will spin easily with plugs out-no compression BUT you will be able to see if sparking good and color indicating strength of spark or if either has none.
 
what dos that mean ? If the coils are set too far back from the magneto there won't be any spark at all, isn't that the problem ?all those new parts and still no spark-kill switch on that model ?
 
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