CDI Electronics Outboard Ignition Troubleshooting Guide

37 Johnson/Evinrude Troubleshooting Johnson/Evinrude the coil). 7. Swap the ignition coil with one that is sparking correctly. 8. Rare causes include a weak trigger magnet. If possible, try another flywheel. POWER PACK OR TIMER BASE REPEATEDLY BLOWS ON SAME CYLINDER: 1. Check the timer base wires for shorts to engine ground as a shorted timer base wire can destroy a SCR inside the power pack. 2. In contrast, a shorted SCR inside the power pack can destroy a timer base coil. Check the timer base resistance and DVA output (see NO SPARK ON ANY CYLINDER above). 3. Replace the ignition coil on the cylinder dropping spark. ENGINE WILL NOT SHUT OFF: Disconnect the stop wire at the power pack. Connect a jumper wire to the stop wire from the pack and short it to engine ground. If this stops the pack from sparking, the stop circuit has a fault. Check the key switch, harness and shift switch. If this does not stop the pack from sparking, replace the power pack. Repeat test as necessary for additional packs. MISS AT ANY RPM: 1. Disconnect the Yellow wires from the stator to the rectifier and retest. If the miss clears, replace the rectifier. 2. In the water or on a Dynameters, check the DVA output on the Orange wires from the power pack while connected to the ignition coils. You should have a reading of at least 150V DVA or more, increasing with engine RPM until it reaches 300-400V DVA maximum. A sharp drop in DVA right before the miss becomes apparent on all cylinders will normally be caused by a bad stator. A sharp drop in DVA on less than all cylinders will normally be the power pack or timer base. 3. Connect an inductive tachometer to each cylinder in turn and try to isolate the problem. A high variance in RPM on one cylinder usually indicates a problem in the power pack or ignition coil. Occasionally a timer base will cause this same problem. Check the timer base DVA voltage (see NO SPARK ON ANY CYLINDER above). 4. Perform a high-speed shutdown and read the spark plugs. Check for water. A crack in the block can cause a miss at high speed when the water pressure gets high, but a normal shutdown will mask the problem. 5. Check the triggering and charge coil flywheel magnets for cracked, broken and loose magnets.