Re: ’79 9.9 OMC, Power pack CD2 question

[johnyrude200]

The first few years of this motor did not include a fiber washer between the pack and the exhaust bypass cover bosses. You should remove the pack and place fiber washers between that and the powerhead to reduce the melting risk. The ground can be put on the upper left exhaust bypass cover or another convenient location; be sure to use a star washer to insure a good ‘grab’ of the pack grounding wire.

If the pack wire(s) are fused to the pack, replace them for obvious reasons, because you’re on borrowed time.

If you’re SURE you have a bad coil, then just replace that coil and the pack. OR, you can swap leads from the pack to the coils to see if you have a 1/2 dead powerpack, which is fairly common. This will rule out a bad lower or upper coil.

If you had NO SPARK, then you need to look at the pack or the charge coil (ohm it out). They are relatively simple ignition systems to figure out what is wrong.

Keep in mind all you need is a bad or misconfigured ground for any of these components to shut off ignition power. Over the years people pull coils and don’t bother to replace components correctly. Stupid things such as that can stop the ignition system, or corrosion build up, mouse pee, salt, etc. Doesn’t take much to stop it but also doesn’t take much to correct it. Much easier to deal with than points, condensers, and coils in terms of diagnosing a problem. Fewer points to fail.

Last food for thought: if that pack is melting down you should probably look at your cooling system. Use an electronic thermometer (laser type) and run the motor WOT for 5 mins. Check the top of the cylinders, and the sides of the cylinders (on the port side near the head). It shouldn’t be getting much above 150°. Make sure your thermostat isn’t stuck shut or the water pump has failed, or you might have a collapsed water tube grommet under the powerhead (unusual for that year because they switched to a more troublesome style in 1980 if memory serves correct). Possible to just flat out have a clog st tge thermostat too. Leaves, sand, salt, and random bad luck do funny things to the small motors.