Reply To: Evinrude Speed Twin 21.1 HP

[Tom]

I am assuming you have a handheld meter that’s not self-ranging.

With the meter set at 10 kohms or higher touch the two probes together and make sure you get a reading close to zero.  Then probe the two locations where the wires are soldered to the coil.  You should get something between 2 kohms and 6 kohms (2000 to 6000 ohms).  If you get no reading, the coil is open, and shot.  Let’s assume the reading is good.

Set the meter to the lowest reading, and probe one wire at the coil and at the spark plug end of the same wire.  Reading should be close to zero.  Repeat for the other wire, hope for the same reading.  If these readings aren’t low, someone may have used the wrong wires, they should be copper core.

There should be two wires coming from the coil.  One is grounded to the mag plate, the other goes to the points.  Remove the condenser, or unscrew it from the mag plate and isolate the can from the mag plate with a rag.  It’s OK to leave the wire connected to the points.  Put a piece of paper between the points.  Measure resistance between the mag plate and where the coil wire is soldered or screwed to the points.  Reading should be close to zero.  If it’s open, the primary side of the coil has problems.  This is extremely unlikely.

If all of this checks out, replace the condenser.  There are alternatives to finding an original one.  If you go with the newer discrete components, shoot for something like 0.3 uF.

Photos are good to see, keep us posted.  Given that someone has been in there, post a few photos here or send them to my email.  You can find my email address in the Members Only section.

Tom Manley, Mansfield, MA