1988 OMC 2.3 Ford - No Spark at Coil

PUFFY

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Jul 22, 2006
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Had the boat on the water - was running fine at about 3600rpm when it suddenly shut off - it would crank over but wouldn't start - have no spark at coil - got towed in - after reading many responses on this site, here is what I have tested. I unplugged the ESA and still no spark - with the key in the "on" position I disconnected the 2 wires on the + side of coil - connected alligator clip of test light to the 2 wires-touched the + side of battery and I got "light" - when I reversed the procedure there was no light. according to wiring diagram one wire comes from the alternator and one from the solenoid. Should the 2 wires be grounded as they indicate with the test light? Also read that the grey wire (tach) on the - side of coil can cause no spark if there is a short. Any answers??
 

bruceb58

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Mar 5, 2006
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Re: 1988 OMC 2.3 Ford - No Spark at Coil

Are you sure one of the wires goes to the coil directly from the alternator? Usually, it would go through a ballast resistor. if it does go straight to the coil you have an internal reistor in the coil.

I would get a multimeter and measure the voltage at the coil with respect to ground with the points open and closed.

I would remove the wire going to the tach as a test.

Take all the wires off the coil and measure the resistance of the primary. Should be around an ohm or two if you have an external ballast resister type coil. It could be 4 ohms higher if you have an internal resistor in the coil.

The resistance between the positive side of the coil and the high tension output should be around 10K ohms.

Do you have a dwell meter? You can see if you have proper dwell by hooking it up and cranking the engine.
 

Boatin Bob

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Sep 24, 2001
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Re: 1988 OMC 2.3 Ford - No Spark at Coil

On those engines the wire coming from the alt is the resistor wire. Take the 2 wires off the pos side of the coil and use a meter with the other wire going to ground. The wire from the start solenoid should have 12v with the key turned to start, the resistor wire should be around 8-9v with key at the ON position. Also check inside the dist for the points, if they don't close or never open, no spark.
 

PUFFY

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Jul 22, 2006
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Re: 1988 OMC 2.3 Ford - No Spark at Coil

the points are opening so don't believe that is the problem - I don't have a meter but am using a test light - my question is: how come when I take the two wires off the + side of coil and put the alligator clip on them with the test light I get a light (the ignition is in the "off" position) (isn't that an indication that they are grounded) and when I put the clip on a ground and touch the wires with the light - there is no light but the wires get hot (to touch) and this is with the ignition in the "on" position
 

bruceb58

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Re: 1988 OMC 2.3 Ford - No Spark at Coil

When you say "I take the two wires off the + side of coil and put the alligator clip on them with the test light I get a light (the ignition is in the "off")", does it do this with each wire seperately or tied together? I am assuming when you are doing this you have one side of the test light on ground and one connected to the coil wires? It almost sounds like you have one side of the test light tied to +12v and the other going to the coil leads which is the wrong way to do it.

You need to do your tests with a meter. A test light can be fine for certain applications. This is not one of them. If you don't have a meter, buy one, take some measurements and let us know what you get.
 

PUFFY

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Jul 22, 2006
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Re: 1988 OMC 2.3 Ford - No Spark at Coil

I will be getting a meter tomorrow but want to clarify how I did the tests - the two wires on the + side of coil are together as "one connector"
1st test - with the ignition switch in the "on" position I have the alligator clip on the "one connector" and then I put the test light on +12v - this produces "light" - this tells me that the "connector" is grounded - am I right?

2nd test - with the ignition switch in the "off" position - I attach the alligator clip to +12v and then touch the "one connector" with the light - this produces "no light" but the wire gets warm to the touch

after I get the measurements, I will post the results. Thanks for your input
 

Boatin Bob

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Sep 24, 2001
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Re: 1988 OMC 2.3 Ford - No Spark at Coil

I'm not really following how you are doing your testing, your making this much more complicated than it needs to be, are the wires still attached to the coil on the second test, if so It sounds like you are actually trying to charge the coil through the test light. As mentioned get the meter, you can also do a continuity test through the points. Just looking at the points is not good enough, they need to open and close and be clean to allow the ground signal to go through. Meter each of those pos coil wires off the coil. The purple/red wire is the resistor wire and should have 8-9 volts wiht key in the ON position. The purple/black wire comes from the start solenoid and should have 12v when key turned to start. Make sure you put the negative wire from the meter on a good ground.
 

bruceb58

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30,588
Re: 1988 OMC 2.3 Ford - No Spark at Coil

Both of your tests were done incorrectly.

Should have had the one side of your test light to ground.

I have no idea what you were trying to do with your second test.

Just to clarify something that Bob said. You will measure 12v at the coil with the ignition on and with the points open. It will be 8V with the points closed.
 
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