I've had the HD-15 running a few times since I went thru it,
probably 10 minutes the longest run time, but it never
ran good enough to tune in the carb. It was only
running at higher speeds, and acted like an
ignition problem. I don't think it was dropping
a cylinder, but can't be sure, but both plugs
seemed equally "hot" to the touch.
The last few times I tried to run it, after playing
with the mag, looking for things wrong, it's
only gone "down hill", and the spark may not
be as strong.
I checked it out today, and the best "air gap"
spark jump I can get consistently is only 1/8" +
Previously I swapped the new .17 mfd condenser
for an "orange drop" .20 cap just in case I had
a bad condenser, but guess not.
Retested what I could today .......
-Coil Secondary 6.29 K ohms
Primary .8 K
-Kill Post working as designed
-Flywheel magnets - "So-so to Iffy"
-Flywheel brass grounding contact to "ground", "0 to .7" ohms resistance.
-The carbon brushes have good continuity to the coil,
and not grounded out anywhere.
-New plug wires with good readings at terminals.
Mumbles mentioned in a previous threadviewtopic.php?t=11555
about taking the bakelite plate (with brass contact)
out of the flywheel and replacing the contact
If you're listening Mumbles, how to you re-attach this
plate to the flywheel after replacing the spring?
It appears to be held on with three rivets, from the
top of the flywheel, but they don't go thru the
Also, regarding the flywheel magnets, did Johnson
ever have an actual test to measure the required pull or
strength of the magnets?
I spent a fair amount of time on the power head,
new rings, tightening up the crankcase clearances, etc.,
so I'd like to see this one be an actual runner!