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Troubleshooting OMC Battery CD ignitions

********      This information is supplied as a service guide only and Outboardparts.com is not liable for any misunderstandings, errors or omissions regarding this information. The information has been obtained from actual Unit analysis, parts manuals, and other sources.      ********

 
Recommended Tools:
for DVA: Fluke Multimeter with CDI #511-9773 Peak Adapter, (or CD-77) and CDI #511-9770
CDI #511-9701 Battery CD Tester
CDI #511-9766 Spark Gap Tester
Jumper Wires
A Reliable Volt/Ohm Meter (if the CD-&& is used for the DVA
CAUTIon; DO NOT Use A FREE Battery with these TypeS of ignitions As theY TEND To OVERCHARGE and BLOW the Packs.> Typically 17 Volts +.
 
Note: A large portion of the problems with the battery CD units are caused by low battery voltage or bad ground connections or high battery voltage.  Low Voltage symptoms are weak erratic firing of cylinders. Misfiring after a few minutes of running can be caused by excessive (Over 15.5 Volts DC) voltage at the pack - See #2 below.
  
1) Check all battery and ground connections.
 
2) Check the Voltage on the red (or purple) Wire at the CD Unit.
If the voltage is less than 9 1/2 volts during the cranking there is a problem in the battery circuit. These units require at least 9 1/2 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 above. If low, replace the battery and retry. Warning: Check he voltage on the red (or purple) Wire at the CD Unit through the RPM range. At no time should the voltage exceed 15.5 Volts DC.
   
3) Disconnect points and/or sensor Wire and connect a battery tester.
Hook up the Battery CD Tester according to the operators manual and align rotor with spark plug Wire. Connect a spark gap to all spark plug wires and turn the Ignition switch on. If the CD Unit fires only to one spark plug Wire, check the points, sensor, anti-reverse spring and wires for breaks and 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 (511-9701) is not used, strike points Wire against engine ground. for the sensor, strike the two wires together. The CD Unit should fire every time. If the CD Unit fails to fire, it is usually bad.
   
4) Points type Ignition.
Disconnect points Wire and check voltage on the points Wire. You should read close to battery voltage with the key switch on. No voltage means a bad pack. If OK, reconnect the points Wire. Using the piercing probes (511-9770) connect the DC volt meter to the points Wire. Turn the switch on and slowly rotate the flywheel. You should see the voltage fluctuate up and down.
   
5) Check the Ignition coil.
An open, cracked or poorly grounded coil can burn out a battery CD Unit.
   
6) Check the DVA voltage on the primary input Wire to the coil.
Reading should be approximately 200 volts or more.
   
7) Simplified bench test:
  cdiomctrouble.jpg (15108 bytes)

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