*&#$& grande wiring/spark issue

I've tried everything I can think of to get this spark, including wiring up a totally new harness (already wanted to, just seemed like the right time to do it) and replacing condensor, points, and ignition coil. The only hope I have left is in a funny wiring diagram

"grande diagrams":http://www.mopedriders.org/html/manuals/piaggio/grandeap/grandeap.htm

(pages 11 & 12)

On the diagram it looks as though the red wire should be coming from the coil with thinner magnet wire and more "turns", and the blue wire should be coming off the coil with thicker magnet wire and less "turns". However, the way my engine is wired (and this is the way it came, mind you) the blue and red wires are coming off the opposite coils the diagram seems to suggest. Does anyone know if the diagram is just confusing me, or if those wires need to be switched?

If this isn't the issue, I have no idea what to do. Is there maybe a way to check and make sure all the wires carry a current so I know the wirings not bad?

Thanks a bunch,

Hank

Re: *&#$& grande wiring/spark issue

Bruce Wilkinson /

After looking at the diagram , the coil with the red wire only has the one red wire coming out of the magneto which goes to the horn. The other end of the coil is grounded. But the coil with the blue wire also has a violet wire. I do't know if this helps at all.

Re: *&#$& grande wiring/spark issue

Hanky B /
hank OP

yeah, I've got all that, i'm just wondering if the wires are hooked up to the wrong coils.

Hank

Re: *&#$& grande wiring/spark issue

Bruce Wilkinson /

If the wire from the horn goes to the coil with the one wire then it is right. If it goes to the one with two wires then it's wrong.

Re: *&#$& grande wiring/spark issue

Bruce Wilkinson /

Do you or did you have turn signals on that moped ? I have another wiring diagram for the turn signal model. It has 3 coils inside the magneto.

Re: *&#$& grande wiring/spark issue

Hanky B /
hank OP

the red wire from the horn DOES go to the coil with one wire. That's confusing though, why does the diagram look like that coil should have more windings, when on the actual engine, the other coil has more windings?

Also, as far as I know it has never had turn signals or 3 coils, so I should be okay there, but thanks.

Hank

Re: *&#$& grande wiring/spark issue

Bruce Wilkinson /

Maybe zippy can help you . email him, zippymoped@yahoo.com

Re: *&#$& grande wiring/spark issue

Piaggio mopeds will not spark if the brake light bulb is burned out or non existant.. Just a thought. Maybe something that simple IS your problem.

Re: *&#$& grande wiring/spark issue

Hanky B /
hank OP

Something that simple HAS to be the problem, I just can't find where it is. I've checked the bulb half a dozen times now, and each time I'm disappointed to find it's okay. I'm heading out this morning in search of a functional ohm-meter so I can check to see that current will in fact flow through all my different connections. If that doesn't work my dad told me to push it into the lake. Hopefully it doesn't come to that.

Hank

Re: *&#$& grande wiring/spark issue

Damn Gremlins... Good luck Hank...

Re: *&#$& grande wiring/spark issue

Hanky B /
hank OP

Yes it is a gremlin, but I've narrowed down where he lives! It seems when:

(1) the engine is disconnected from the wiring harness and (2) the points are open, the wires connected to the points are NOT grounded.

This is correct because if they were grounded, there would be no reason for the spark plug to spark to ground.

HOWEVER, when (1) the engine IS connectected to the wiring harness and (2) the points are open, the wires connected to the points ARE grounded. because of this, there is no reason for the spark plug to live up to its name.

Hopefully this faulty ground is an easy find.

God bless you multimeter, and thanks you guys for the advice and encouragement!

Hank

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