Re: How to check coils on 1986 110 Johnson
Use a simple 1.5 volt flashlight battery on the primary (connection where the coil and points are connected) and ground (or as the case of a solid state module, the coil primary lead from that module.) Polarity doesn't matter but always disconnect the coil from the module to prevent damage to the module. As you flash the correct connection to the flashlight battery the secondary of the coil should produce a consistent though weak arc on the spark plug gap. Remember your using 1.5 V and not the strong magnets of the flywheel to excite the coil. Compare the strength of the arc to that of a known good coil or to others on multi-coil motors. If a tested coil falls short in a comparison, replace. Be careful or you will get shocked. If you attempt to do the test with the points still connected you will have to make sure the points are open and remember the condensor is still in the circiut so another possible cause of loss of spark. Most of the time the primary of the coil can be disconnected easily from the motor while leaving the secondary and spark plug connections intact for this test. Ron