Mercury KE4 Ignition

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    goldmember


    Replies: 36
    Topics: 15
    #160253

    Hello,

    Brand new to this hobby as I picked up a 1948 Mercury KE4 for free. It is in great shape but it has been sitting in a barn for 20 years. While trying to resist the urge to take it completely apart I have decided to do a few things first to determine if it is worth it. Easiest thing is a carb re-build and clean. But the ignition stumps me.

    I have determined through the service manual that I have the Scintilla ignition and I removed the coils to bench test them on an auto ranging Fluke meter.

    Primary reads 3.2 Ohms on both coils and secondary reads 5.7 on one and 7.2 on the other. Both have cracked casings.

    Are these BAD? If they are I have read that there is an obtainable replacement that fits the frame and has the same performance characteristics as the Scintilla with some modifications. Does anyone have instructions on this?

    seakaye12
    seakaye12

    US Member - 2 Years
    Replies: 493
    Topics: 116
    #160259

    I would start with a spark check; see if it will consistently produce a bright white spark that will jump a 1/4″ gap. The cracks are of course a very bad sign. The coils will need to be replaced at some point even if they seem to work now….but they might last long enough to allow you to evaluate the running quality of the engine. New coils are expensive; better to know that the engine is worthy of that first.

    There are surplus military coils that some people have successfully modified. The connection for the spark plug wire is in the wrong place….and it needs to be soldered. They currently can be had for under $20.00 on ebay. The last time I looked; oldmercs.com had the “correct” coils for $80.00.

    • This reply was modified 1 year, 3 months ago by seakaye12seakaye12.
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    goldmember


    Replies: 36
    Topics: 15
    #160265

    I get a spark on one coil and an occasional spark on the other. Is there a video or white sheet on the military coil conversion?

    Also, what do you use to lubricate the slide lever for the throttle

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    kerry

    US Member - 1 Year
    Replies: 350
    Topics: 17
    #160267

    The coil conversion uses easy to find OMC coils. Lets see if this link works… https://www.youtube.com/watch?v=OxPHe8EPe1Q

    If you have too many, AND not enough, you're a collector.

    seakaye12
    seakaye12

    US Member - 2 Years
    Replies: 493
    Topics: 116
    #160268

    OMC coils can be used on the Phelon version of Mercurys.

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    goldmember


    Replies: 36
    Topics: 15
    #160274

    Does it work for the Scintilla version

    mercuryman
    mercuryman

    US Member - 1 Year
    Replies: 384
    Topics: 146
    #160281

    You may think your points are clean but when you can read 1 ohm or less across the points they are clean and you should get spark. You need to unhook the coil to do this test.

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    dave-bernard

    US Member - 2 Years
    Replies: 1017
    Topics: 14
    #160301

    NO OMC wont work on scintilla.

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    Replies: 36
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    #160305

    Okay, so what works for Scintilla

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    dave-bernard

    US Member - 2 Years
    Replies: 1017
    Topics: 14
    #160316

    What SeaYack had to say.

    Tubs
    Tubs

    US Member - 1 Year
    Replies: 2788
    Topics: 161
    #160357

    The coils for you magneto are no longer being
    manufactured. This coil is the same except for
    the location where the plug wire attaches and
    it needs to be soldered on. I believe other here
    have used them. (Link below)

    As far as using the OMC coils mercuryman
    was experimenting some substituting them.
    I don’t know how that worked out.

    https://www.ebay.com/itm/1A08-2A016-Military-Standard-Engine-Coil-Standard-Ignition-P-N-9786E128/273582440804?epid=1831582541&hash=item3fb2c8c164:g:4fIAAOxy3zNSoMlB:rk:1:pf:0

    • This reply was modified 1 year, 3 months ago by TubsTubs.
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    chuckw

    US Member - 2 Years
    Replies: 65
    Topics: 4
    #160398

    If the coils are cracked, they may spark but when warm from running may fail.

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    chuckw

    US Member - 2 Years
    Replies: 65
    Topics: 4
    #160399

    I have two of those. Buzz Lindberg (“creekrunner” here) has a neat way of adapting them for the scintilla mags.

    RICHARD A. WHITE
    RICHARD A. WHITE

    US Member - 2 Years
    Replies: 1729
    Topics: 132
    #160414

    I used 2 of those in a Chriscraft Challenger. Good hot blue spark.. The output was in an awkward place, but some liquid electric tape solved the issue. I have photos but they are on my phone right now.

    http://www.richardsoutboardtools.com
    classicomctools@gmail.com

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    jeff-register

    US Member - 1 Year
    Replies: 1159
    Topics: 48
    #160426

    No one agrees with me but you can coat them with Super Corona Dope, a very high voltage insulation that looks like clear finger nail polish from MG chemicals. Once the cracks are filled wrap with radio controlled airplane very thin fiberglass cloth & recoat. What is the resistance from plug wire to ground? Once the coil is clean look for pits where the coil may have arced to ground. There is two coil windings, primary &; the secondary winding, the wire used is finer than a humane hair & damaged easy. Running without having the plug wire off the spark plug has produced energy & will arc to the magneto plate.

    Also don’t forget the capacitors, they fail too & will not give a good spark. They are 2 pieces of foil separated by wax as an insulator. The wax shrinks with time & shorts out the foils.
    Top seal may be bad blowing fuel on the magneto causing no spark too, was it wet?

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