1987 2.3 OMC Cobra - sputtering

Seguin

Recruit
Joined
May 30, 2011
Messages
3
Hi
I have a 1987 2.3 OMC Cobra I/O on a 17' bayliner capri and it ran great for about 20 minutes and then wouldn't run above 2000 rpm without sputtering and bogging down.
After a long process of elimination (battery, alternator, coil, points, condenser, ignition switch, 20 gauge wire that acts as the ballast resistor, 50 amp fuses, spark plugs and spark plug wires, fuel pump, carburator kit, fuel tank/lines/filters/vents/check valve) I solved the problem.

The problem was in a section of the primary circuit of the ignition system:

1. the 20 gauge resistor wire to the positive post of the ignition coil.
2. the wire from the negative post of the coil to the distributor.
3. the distributor ground plate.
4. the ground plate screw to ground.

I replaced the wires (Ancor 20 gauge dual speaker wire for the resistor wire), buffed up all of the connections, and used dielectric silicone compound sparingly on the condenser and contact point bases just where they are mounted to the distributor ground plate

Also, I added a new ground wire from one of the distributor ground plate bolts (engine side in my case) to the lower mounting bolt for the starter solinoid. This was the only addition to the original electrical system.

I also used an OMC tune-up kit with an OMC condenser, contact points, and rotor.


I hope this is helpful.
Seguin
 
Joined
May 18, 2011
Messages
23
Re: 1987 2.3 OMC Cobra - sputtering

goto www.kencook.com and they have original owners manuals, service manuals and parts manuals. the service man is great and the parts man has exploded views with part numbers.
 

deannasmith

Recruit
Joined
Aug 22, 2011
Messages
1
Re: 1987 2.3 OMC Cobra - sputtering

Where did you get the spark plugs?




Hi
I have a 1987 2.3 OMC Cobra I/O on a 17' bayliner capri and it ran great for about 20 minutes and then wouldn't run above 2000 rpm without sputtering and bogging down.
After a long process of elimination (battery, alternator, coil, points, condenser, ignition switch, 20 gauge wire that acts as the ballast resistor, 50 amp fuses, spark plugs and spark plug wires, fuel pump, carburator kit, fuel tank/lines/filters/vents/check valve) I solved the problem.

The problem was in a section of the primary circuit of the ignition system:

1. the 20 gauge resistor wire to the positive post of the ignition coil.
2. the wire from the negative post of the coil to the distributor.
3. the distributor ground plate.
4. the ground plate screw to ground.

I replaced the wires (Ancor 20 gauge dual speaker wire for the resistor wire), buffed up all of the connections, and used dielectric silicone compound sparingly on the condenser and contact point bases just where they are mounted to the distributor ground plate

Also, I added a new ground wire from one of the distributor ground plate bolts (engine side in my case) to the lower mounting bolt for the starter solinoid. This was the only addition to the original electrical system.

I also used an OMC tune-up kit with an OMC condenser, contact points, and rotor.


I hope this is helpful.
Seguin
 

Seguin

Recruit
Joined
May 30, 2011
Messages
3
Re: 1987 2.3 OMC Cobra - sputtering

I got my plugs at VIP auto in Yarmouth, Maine this year, but I've bought plugs at NAPA also.
Champion Spark plugs: RS12Y-C
 

goldcoastgreg

Recruit
Joined
Sep 3, 2011
Messages
1
Re: 1987 2.3 OMC Cobra - sputtering

I was wondering if the "dual speaker wire" gives the circuit the proper resistance as to avoid premature failure of the points and such . I read on another post that resistance across the coil should hang around 3 ohms, + post to -post of the coil , and that cranking voltage should be 12 volts+ and reduced to 9v while running, +side of coil to ground. have you checked the resistance of the wires mentioned? And the running voltage, + side of coil to ground ?
 

Seguin

Recruit
Joined
May 30, 2011
Messages
3
Re: 1987 2.3 OMC Cobra - sputtering

The dual speaker wire is a dual 20 gauge wire. I use one of the two wires.
The original resistance wire is 20 gauge and I just cut a piece the same length to get the same resistance.
 
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