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Can I test Tecumseh Coil?

Posted by seakaye12 (My Page) on
Thu, Jun 21, 07 at 11:26

Hi All,

I have a Tecumseh engine on a Sears Outboard .It's vintage 1970; 5HP engine tag #643-15 #6324102 I just acquired it and find it to be in good shape except it has a very weak/intermittent spark.

I replaced the condenser and cleaned the points (they look new). Still no spark.

The magnet on the flywheel seems I suppose that by the process of elimination it must be the coil?????

The coil certainly looks fine; as does all the wiring. Is there a way to test it????? I think it's part #30560A

Thanks, Chuck

Follow-Up Postings:

RE: Can I test Tecumseh Coil?

Yes,if you can find a small engine shop with a "merc-tronic" tester,you can have the coil tested ....I would buy new points also ,I think you'll find the coil good....ole points should be replaced ,Good Luck,Jim

RE: Can I test Tecumseh Coil?

Some shops will also use a Graham tester, which also tests
the coil, same as the Merc-O-Tronic tester. The 30560A coil
is pretty common and most shops will still stock them. I
would replace the coil, if you've already replaced points
and condenser. These magneto systems need to be "TIMED".
Without proper measurement tools, it's a tedious and a hit
or miss proposition. If you know of a shop that's familiar
with the timing procedure, I'd let them set it for you.
This actually needs to be done EVERY TIME the points are
replaced, or ANY service is done on the ignition system.


RE: Can I test Tecumseh Coil?

  • Posted by canguy British Columbia (My Page) on
    Thu, Jun 21, 07 at 23:35

LOL. I got parked on my keester using the Merc-O-Tonic a couple of times. I still have the timing tools in my kit but no dial gauge.
As long as you don't disturb the throttle cam setting on the mag you should be o.k.but like T-man says, the engine will work best if the timing is checked every time (and those damn Tecumseh 2 strokes need all the help they can get).

RE: Can I test Tecumseh Coil?

Hmmm...Sounds kinda like what outboard wrenches call a "lync and synch"......

There is an adjustment that controls the point that the magneto plate starts to open the throttle plate on the carb.

I don't really see any other adj that would be possible? Can any of you explain further just what/where the timing adj is made?

Right now...I do notice that the throttle plate is a bit shy of opening all the way when the magneto plate is fully advanced. I thought this might be odd...and was planning on playing with it a bit once I got the beast running.

Maybe there's a PDF somewhere out there that describes the timing procedure?

Thanks for your time guys...I appreciate it. This motor is the summer project of a pre-teen neighbor. He has enlisted me to help him out. He's a good kid; I hate to let him down :)


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