Coil Prob

[capthook]

Hello again all. Well I am not getting much responce to my other post so I thought about putting up another. Here is my problem. This is a 73 reinnel with a 140 mercruiser 4 cly. I am not getting any spark to my coil. Only when I turn the key on and off will I get spark. When I am cranking on the engine I get nothing. So when I am turning the key on and get spark this is telling me that my resister wire is working. Why am I not getting spark when cranking. I just put in a new ignition switch just like the old one and still NOTHING! Anyone had similar issues or suggestions. Thanks everyone.

 

[Mischief Managed]

Re: Coil Prob

I suspect there's a ballast resistor bypass in the starting circuit. If there is one, it allows the full battery power to reach the + terminal on the coil only while the starter is engaged. Once the starter is no longer in use, the battery voltage needs to pass through the ballast resistor (voltage drop) to get to the coil. Perhaps soemthing in this circuit is bad. I'd look at the starter solenoid first. The bypass wire is likely purple and yellow. <br /><br />Try connecting the + side of the coil directly to the battery + with a temporary jumper and see if it runs. Can't leave it on for long though, or the coil will overheat.

 

[capthook]

Re: Coil Prob

Thanks I will try that. Will I need to disconnect the other wires while doing this. I would guess so since the control the voltage or I will still be in the same position.

 

[Bt Doctur]

Re: Coil Prob

good chance the points or condenser are some how grounding out or the shift interupter is activated and grounding the system out..to have spark the points need to open and close. if there not opening at all ,turning the key to off will create a spark from the field in the coil collapsing.