CDI Electronics Outboard Ignition Troubleshooting Guide

84 TROUBLESHOOTING GUIDE - Mercury Troubleshooting Mercury Troubleshooting approximately 7/16”. Align the rotor with #1 spark plug wire. Turn the ignition switch on and strike the Brown points wire against engine ground (Or use a CD Tester). Only the #1 spark plug wire should spark. If any other spark plug wire now has spark, there is a problem in the distributor cap. Repeat the test for the other cylinders. 9. Perform a voltage drop test after the engine is repaired to see if there is a problem with the voltage going to the CD module. At cranking and while the engine is running, use a DC voltmeter and put the Black meter lead on the battery POS (+) post and the Red meter lead on the positive battery cable at the starter solenoid. Keep the Black lead on the battery post and shift the Red meter lead to the positive post of the rectifier, then to the Red and White terminals on the switch box. If you find a reading above 0.6V, there is a problem at the point where the voltage jumped up. For example, if the meter reads 0.4V until you get to the White terminal and then jumps to 2.3V on the White terminal – this indicates a problem in the key switch, or harness. Repeat the test for the negative battery post by putting the Black meter lead on the battery NEG (-) post and the Red meter lead on the negative battery cable terminal, then shifting to the engine block, rectifier base and case ground of the CD module. Mercury Battery CD Ignitions without Points Three Cylinder Engines (With 114-4796/ 3 32-4796/393-4797 Switch Box) (Note) A CD Tester by CDI Electronics ( 511-9701) or Merc-o-Tronics can be used to test the CD module, distributor cap, rotor button and spark plug wires on the engine while the Trigger Tester by CDI can be used to test the distributor trigger. (SERVICE NOTE) Check the battery voltage at approximately 3500 RPM, MAXIMUM reading allowable is 16 volts and minimum is 12V. Running below 12V or over 16 volts will damage the ignition. Check for loose connections or a bad battery. Maintenance free batteries are NOT recommended for this application. Engine Wiring Connection for Testing Ignition Module GENERAL: 1. Clean all battery connections and engine grounds. 2. Disconnect the mercury tilt switch and retest. If the ignition works properly, replace or discard the mercury tilt switch. 3. Connect a spark gap tester to the spark plug wires and check for spark on all cylinders. If some cylinders spark and not others, the problem is likely in the distributor cap, rotor button or spark plug wires. 4. Perform a voltage drop test after the engine is repaired to see if there is a problem with the voltage going to the CD module. At cranking and while the engine is running, use a DC voltmeter and put the Black meter lead on the battery POS (+) post and the Red meter lead on the positive battery cable at the starter solenoid. Keep the Black lead on the battery post and shift the Red meter lead to the positive post of the rectifier, then to the Red and White terminals on the switch box. If you find a reading above 0.6V, there is a problem at the point where the voltage jumped up. For example, if the meter reads 0.4V until you get to the White terminal and then jumps to 2.3V on the White terminal – this indicates a problem in the key switch, or harness. Repeat the test for the negative battery post by putting the Black meter lead on the battery NEG (-) post and the Red meter lead on the negative battery cable terminal, then shifting to the engine block, rectifier base and case ground of the CD module.