Boat parts & accessories for Johnson, Evinrude, Mercury, Mariner, Force, or Yamaha outboard motor, & Mercruiser, OMC stern drive. 

  Johnson Evinrude Outboard Ignition Troubleshooting Tips

Battery Ignitions

A large portion of the problems with the battery CD units are caused by low battery voltage and/or bad ground connections. Low voltage symptoms are weak fire or weak erratic firing of cylinders.
1) Check all battery and ground connections.
2) Check voltage on the red (or purple) wire at the CD unit. If the voltage is less than 9.5 volts during cranking, there is a problem in the battery circuit. These units require at least 9.5 volts to fire properly. Connect a jumper wire directly from the battery(+) terminal to the red (or purple) wire. Retest. ATTENTION: In order to kill the engine if it cranks, the jumper wire must be disconnected and/or choke the engine. If the engine still fails to crank, recheck voltage as mentioned above. If low, replace battery and retry.
3) Disconnect points and/or sensor wire and connect battery tester. Connect the battery CD tester according to the instructions on the back and align rotor with spark plug wire. Connect a spark gap tool to all spark plug wires and turn ignition switch on. If the CD unit fires to only one spark plug wire, check the points, sensor, anti reverse spring, and wires for breaks or shorts. IF ANY other spark plug wire fires besides the one the rotor is aligned with, the distributor cap and rotor should be replaced. The battery CD tester will fire the system to approximately 3000 RPM. If the battery CD tester is not used, strike points wire against engine ground. For the sensor, strike the two sensor wires together. The CD unit should fire every time. If the CD unit fails to fire, it is usually bad.
4) Check the ignition coil An open, cracked, or poorly grounded coil, can burn out a battery CD unit.
5) Check the DVA voltage on the primary input wire to the coil. Reading should be approximately 200 volts or more.
6) Simplified bench test

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Power Packs & CD's
1) Check the flywheel for cracked and/or loose magnets. Be sure the magnets are secure and have not moved out of place.
2) Disconnect the kill wire(s) from the pack and connect a voltmeter between the kill wires and engine ground. Turn the ignition switch on and off several times. If at any time you see DC voltage appearing on the meter, there is a problem in the harness, or ignition switch. Note: At no time should you see voltage on any kill wires.
3) Visually inspect stator for cracks or leaks: if found, replace the stator. Burnt marks or discolored areas on the battery charge windings, indicate a possible problem with the rectifier.
4) Unit will not fire:Disconnect kill wire AT THE PACK. Check for broken or bare wires on the unit, stator and timer base. Measure DVA voltage of the stator with everything connected. Readings should be approximately 150 volts or more. On standard CD types, check DVA voltage on the timer base white wire. Voltage should be approximately 150 volts or more (Quick start units usually have the white wire tied to the ground inside the pack). If reading is good on the stator but low on the white wire, the timer is usually bad. Disconnect the rectifier. If the engine fires, replace the rectifier.
5) '88 - ' 96 V6 & V8 Quick start timer bases: Disconnect the timer base using the Fluke meter set to ohms scale and one of the piercing probes, connect the red lead from the meter to the white wire in the Amphenol connector to the timer base. Use the black lead from the meter, and check to all of the pastel colored wires in both connectors from the timer base. All of the readings should be fairly even, normally between 1 & 2 meg ohms measured with the Fluke meter. With the red lead still connected to the white wire, connect the black meter lead to the black/white wire in the opposite connector from the timer base. You should read approximately 220 ohms (440 ohms on the GT 150/175). If one or more cylinders are out of line (i.e. all the rest are reading 1.2/1.8 meg ohms, and one reads 0.898 or 2.2 meg ohms) the timer base is usually bad.
6) '92 - '96 Looper units with optical triggers: DVA check the stator, each set of brown wires should read at least 150 V (950 - 1050 ohms) and 12 volts between the two orange wires from the power coil (50 ohms). Note: These plug connectors containing the kill wires use a jumper wire to connect the kill wires in the pack. If the pack still fires, there is a problem in the harness, safety circuit, or ignition switch. A no fire situation with the jumper in place, indicates a bad pack.
7) '89 - '95 4 cylinder looper unit: If the engine misses on one cylinder with the white/black temperature wire hooked up, and does not with it unhooked, this is usually the timer base causing the problem.
8) For PowerPack 4 units: Cylinder 1 & 3 or 2 & 4 will not fire: Check timer base resistance between 1 - 3 and 2 - 4. Readings should read 10 - 20 ohms on each. Check air gap on sensor coils. If regapping is needed, R97-2 sensor gap gauge is required.
9) Engine will not kill: Remove the black/yellow kill wire from the rubber connector to see if the pin is broken. Check kill circuit in the pack by using a jumper wire connected to the black/yellow wire coming out of the pack and shorting it to ground. If this kills the engine, the kill circuit in the harness or boat is bad, or the ignition switch is bad.
10) Coils fire with spark plugs out, but not in: Check for dragging starter or low battery causing slow cranking speed. DVA test stator and timer base.
11) Engine runs rough on one bank ( 4 and 6 cylinder engines with CD ignition): DVA check stator voltage to both sides. The readings should be fairly equal. If it exceeds 400 volts, replace the pack on that bank. If unequal, swap banks with stator leads and see if the problem moves with the stator leads. If it does, replace the stator. Disconnect one of the black/yellow kill wires AT THE PACK. If the problem is eliminated, replace the pack that was running smooth, as it probably has a bad blocking diode.
12) Intermittent firing on one or more cylinders: Low voltage from the stator or a bad timer base. Disconnect rectifier and retest. If the problem disappears, replace the rectifier.
13) Check for broken wires and terminals: Especially check inside the rubber Amphenol plug-in connectors. We recommend that you remove the pins from the connectors and visually inspect them.

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