I have an '86 2.5L OMC Cobra I/O engine.
I recently changed the ignition points to electronic ignition: http://www.amarket.com/imptmd4.htm. Since my engine has a shift interruptor, I also performed the diode fix: http://www.pertronix.com/support/tips/pdf/diodefix.pdf
Since then, I have a few issues. The engine starts without any problems and revs great when in neutral (except for the odd backfire). The tachometer, however, no longer works. If I remove the grey wire coming from the shift assist fix from the negative coil terminal, replace the screws and just let the wire sit on the coil terminal, the tachometer works intermittently. When in drive, the boat will get to a max of 10MPH (it can usually do betwee 30-35MPH). As I continue driving, the power will slowly be reduced. Trimming the engine practically stalls the engine.
Some of the symptoms tell me it could be a problem with the alternator. Could a bad coil also cause these issues?
I have checked the resistance on the shift interrruptor switches and they appear to be working properly. I have also tried manually activating the switches while in drive to ensure this isn't causing the problem with lack of power.
So, to recap, here are the issues:
1. Some backfiring (almost eliminated since replacing the plugs)
2. Lack of power when in drive
3. Trimming almost stalls the engine
4. No tachometer
What has been done so far:
1. Plugs replaced
2. Electronic ignition installed
3. Carb completely cleaned inside out
4. Shift interruptor switches tested
Hopefully, some of the great minds on these forums can point me in the right direction to help me resolve these issues.
I recently changed the ignition points to electronic ignition: http://www.amarket.com/imptmd4.htm. Since my engine has a shift interruptor, I also performed the diode fix: http://www.pertronix.com/support/tips/pdf/diodefix.pdf
Since then, I have a few issues. The engine starts without any problems and revs great when in neutral (except for the odd backfire). The tachometer, however, no longer works. If I remove the grey wire coming from the shift assist fix from the negative coil terminal, replace the screws and just let the wire sit on the coil terminal, the tachometer works intermittently. When in drive, the boat will get to a max of 10MPH (it can usually do betwee 30-35MPH). As I continue driving, the power will slowly be reduced. Trimming the engine practically stalls the engine.
Some of the symptoms tell me it could be a problem with the alternator. Could a bad coil also cause these issues?
I have checked the resistance on the shift interrruptor switches and they appear to be working properly. I have also tried manually activating the switches while in drive to ensure this isn't causing the problem with lack of power.
So, to recap, here are the issues:
1. Some backfiring (almost eliminated since replacing the plugs)
2. Lack of power when in drive
3. Trimming almost stalls the engine
4. No tachometer
What has been done so far:
1. Plugs replaced
2. Electronic ignition installed
3. Carb completely cleaned inside out
4. Shift interruptor switches tested
Hopefully, some of the great minds on these forums can point me in the right direction to help me resolve these issues.
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