Power into coil, no power out=No spark???

[GELRunner]

I have power going into the coil, but not out? I replaced the coil, plugs, cap P&C and rotor on the distributor. When I disconnect my primary wire from the - side of the coil I have power on each side. As soon as I connect the primary wire to the coil then I have nothing. There is only one wire going into the distributor from the coil. I am fairly certain of which wires go where, I took plenty of pictures.

Any ideas on what I'm doing wrong???

History:
I have a 1982 19ft Cobalt w/ OMC 5.7 & 800 stringer outdrive. Just finished putting in a new long block engine, after the previous owner didn't do his winter prep and water was left in and split the block. He didn't want the headache and gave me the boat and trailer which were both in great shape, besides I'm a sucker for a boat with lots of teak!

 

[HT32BSX115]

Re: Power into coil, no power out=No spark???

I have power going into the coil, but not out? I replaced the coil, plugs, cap P&C and rotor on the distributor. When I disconnect my primary wire from the - side of the coil I have power on each side. As soon as I connect the primary wire to the coil then I have nothing. There is only one wire going into the distributor from the coil. I am fairly certain of which wires go where, I took plenty of pictures.

Any ideas on what I'm doing wrong??? !

Howdy, and Welcome aboard!

You probably have a shorted , the points are shorted, or not opening or closing.

If you haven't replaced them, now might be a good time...

Also have a look at the following. http://www.familycar.com/Classroom/ignition.htm


Cheers,


Rick

 

[run2car]

Re: Power into coil, no power out=No spark???

How are you checking for output on the coil?

 

[GELRunner]

Re: Power into coil, no power out=No spark???

I used a test light.

 

[GELRunner]

Re: Power into coil, no power out=No spark???

I think you are right! I need to check to see if I installed the insulator when I changed out the points and condenser, I believe my grounding problem might be right in the distributor!

 

[Canman38]

Re: Power into coil, no power out=No spark???

You can put your tester right on the arm of the points to make sure they are getting a good ground.

 

[HT32BSX115]

Re: Power into coil, no power out=No spark???

You can also test for spark by connecting a spark plug to the center-coil-dist wire. (ground the plug against the something metal-ground.

Then remove the dist cap and rotor, Apply 12v to the "hot" side of the coil.

If the points are closed, open them (by hand). The plug should spark. If they're open, briefly short across them with any suitable metal object (or use an "Alligator-clip" wire etc)

When the points close, they GROUND the (-) side of the coil...on the cam-high, the points are only opened briefly.

There's considerable current flowing through the coil when the points are closed.......(5-10A or more depending on whether there's an ignition resistor and the actual coil resistance)

The "hottest" spark is produced when the current ceases (I.E. points-OPEN).

Not when the current is started (points-close) because the the current rises slower than it when it ceases........ This is why the spark is timed for when the points OPEN. The condenser (simple electronic capacitor) is there to reduce the spark across the points when they OPEN.....so they don't burn quickly. (little arc welder!)

Electronic ignition systems use a solid state device to interrupt primary winding current in the same coil.

Hope this is helpful!


Cheers,


Rick