Mercury KE4 Ignition

[goldmember]

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]

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 5 years, 4 months ago by seakaye12.

[goldmember]

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

[kerry]

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]

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

[goldmember]

Does it work for the Scintilla version

[mercuryman]

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.

[dave-bernard]

NO OMC wont work on scintilla.

[goldmember]

Okay, so what works for Scintilla

[dave-bernard]

What SeaYack had to say.

[Author]

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