No spark on my old Moby

I have been working on my 58 Mobylette for some time and for whatever reason I can't get it to spark. I have installed a CDI unit, new coil and regulator.

The CDI unit has 4 wires coming out of it. Yellow, Green, Black and black with a red tracer. The Yellow wire goes to the regulator, yellow to yellow. Green to green out of the CDI control box. Black to ground and that leaves black/red to what? There is a red wire coming out of the CDI control box, is that what it hooks up to? The Black/white wire coming out of the control box is for the kill switch? Orange out of the control box goes to the coil?

I added an extra ground from the engine to the frame where all the other ground are attached.

Unless the coil is bad? I have no idea what is going on.

Ideas?

Thanks in advance.

John in Texas

Re: No spark on my old Moby

Richard Eberline /

Grounds have to be bare metal clean. The grounds are:

Stator AC coil. black wire

CDI Box. black wire

HT coil make a wire large terminal

Voltage regulator. black wire

Optional ground engine head to frame.

Black with white stipe is kill wire. Not needed use decomp.

Re: No spark on my old Moby

Richard Eberline /

Black with red stripe goes to cdi box.

Orange to ht coil.

Re: No spark on my old Moby

John Ebert /

Well I will go back and clean where the grounds all attach to the frame and build a ground strap from the frame to the engine. I had one going from one of the carb mounting studs to the frame. As someone said you can't have enough grounds.

Thanks

John in Texas

Re: No spark on my old Moby

John Ebert /

Well, I have cleaned up all the grounds. Still no spark.

I thought about hooking my electric impact up and hitting with more spin than my cranking could deliver but that won't work as all I will accomplish is taking the nut off the end of the crank. I have ordered a new coil, not that I know the old is bad it's sort of a hail mary.

Ideas?

John in Texas

Re: No spark on my old Moby

John Ebert /

Is there a way to check the CDI unit and control box?

Thanks in advance for ant help.

John in Texas

Re: No spark on my old Moby

Richard Eberline /

there is a ohm test and a vac test.. With the cdi box installed. For vac test the motor must be spinning. Remove the spark plug and shot in some wd40. Pulse trigger coil and ac coil vac test. Then orange wire to the ht coil and all grounds connected, test. You can test the HT coil with a ohm meter.

Re: No spark on my old Moby

Richard Eberline /

There are four parts a HT Coil, CDI Box and stator plate,/magneto flywheel.

Test

pulse trigger coil VAC

ac coil VAC

cdi box input and output VAC

ht coil OHM Ignition cap and wire OHM

Re: No spark on my old Moby

John Ebert /

I am thinking I need to visit a friend who is more into electronics than I.

Not sure what a VAC test is and how it is done. Time to do more research.

Thanks

John in Texas

Re: No spark on my old Moby

VAC just means AC voltage.

Re: No spark on my old Moby

John Ebert /

We have spark. I had always thought that it was something simple and I was making it harder than it had to be. The nut holding the variator was loose so while I was peddling my heart out it was only occasionally turning the motor. When I used my electric drill and a socket big enough to fit over it, it would spark. Everything is tightened back up. Next is to start her up from a very long slumber.

Thank everyone who gave me advise. Great forum, great people.

John in Texas

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