Rebuilt Magneto '78 Peugeot 103 - No Spark

Hey everyone. First post to the forum, but I have been using all the great info for the past 2 months rebuilding a '78 Peugeot 103 that I got a while back.

I have finally finished cleaning and repairing/replacing everything needed. As I have read up on the issues associated with the old 2-coil Peugeot magneto, I decided to replace everything on the stator plate. Marking everything, careful of the timing, I'm pretty sure I put it all back together on the flywheel very close to the original before removing it. However, I recently tried to turn it over to see that big blue spark, spark. I know the timing shouldn't have anything to do with getting a spark, just a matter of when it happens so timing isn't so much the issue..yet, just no spark. I've taken everything off again re-checked things and tried again, still no spark. I attached a picture of the wiring and setup for reference. The parts I replaced the old with are:

puch and peugeot internal ignition coil/high tension coil -

peugeot internal lighting coil -

- new condensor and points

- new non-resistor ignition wire and boot

- new spark plug NGK BP6HS

I also replaced the brake switches and rewired the braking system to draw power from the lighting coil, so the black wire coming from the old ignition coil is now grounded from between the new coil and stator plate to the frame of the bike.

I also did a check of the coils using a multimeter. I will tell you I'm not savvy when it comes to electrical, and tend to struggle. However I tried multiple positions on the coils testing the resistance at 200 ohm, but got readings of zero. I realize this would mean that the coils are bad, however I cant imagine 2 new coils from treats would both be bad and it is likely operator error.

Also, one thing I was thinking that it could be is the air gap between the magnets and the coil. It seems a little further away from the flywheel that the original coil. Not sure if that would do it, but I would figure I would get a least a soft spark from it.

Any thoughts and comments would be greatly appreciated. Thanks!


Re: Rebuilt Magneto '78 Peugeot 103 - No Spark

Welcome. I don't know Peugeot's but I though since no one's helping I'd try.

Shouldn't the coil go to the condenser? Seems like the black wire from the coil should be going to the condenser where the brown wire is, then run the black to the points? I have had the fun of dealing with points in a while so I'm foggy.

Re: Rebuilt Magneto '78 Peugeot 103 - No Spark

i dont think order matters. but that brown wire is your kill wire i guess. do not ground. u can dremel the slots to move coil closer to magneto

Re: Rebuilt Magneto '78 Peugeot 103 - No Spark

i wouldn't worry about air gap, ive had those coils perform great.

you can test your system dry with a setup something like this:

are you certain your points are opening and closing?

you are right that the timing relative to crank position is basically irrelevant, but those new points can sometimes be finicky.

make sure that nothing in the low tension wiring is grounding out.

make sure you have continuity everywhere in your high voltage side - point to point - and how are you looking for spark - holding the plug against the head? pedaling? drill? spinning by hand?

200 ohm setting is gonna be high to test primary coil resistance - probably not sensitive enough to pick it up .5 - 1.5 ohm depends on the meter. start at lowest setting possible.

run a b6hs or b7hs, dont run a bp.

if you are pulling your hair out, stick it in a box and mail it over to me and ill get it sorted for ya.

Re: Rebuilt Magneto '78 Peugeot 103 - No Spark

lets see a picture of your flywheel for good measure too.

Re: Rebuilt Magneto '78 Peugeot 103 - No Spark

Yeah, I disconnected the kill switch before testing things, so that wire wasn't grounded at all. I had thought about drilling the slots, though a bit nervous about potentially destroying the shoes on the coil.

Re: Rebuilt Magneto '78 Peugeot 103 - No Spark

Thanks for the video. I tried it out and i got a spark, so coil is good. The multimeter I have, its lowest setting is 200 ohm so it might be why I wasn't picking anything up.

Yeah, my points are definitely opening. With the flywheel on, looking through the viewing windows I can see them open as I rotate the flywheel.

Would the wire i have running from behind the ignition coil shoe to the frame of the bike ground out the low tension power. I thought the low voltage was the power coming from the wire exiting the coil to the points. I can also double check my points to see if they could be grounding out on anything else.

I've tried kicking it over with the plug in the boot propped up with the lights off in order to try to see the spark. I've also tried pedaling.

Though at this point it has to be a grounding issue somewhere..right? since I got a spark using the battery test method provided in the video.

I also attached a pic of the flywheel. its slightly rusted on 2 of the 4 magnets.

Thanks for your help.


Re: Rebuilt Magneto '78 Peugeot 103 - No Spark

I would convert it to a Puch ignition unless you really want it this way.

Re: Rebuilt Magneto '78 Peugeot 103 - No Spark

I've seen a little rust kill the ignition but it's usually on the coils not the magnets?? It's definitely not helping so you may want to clean them. I've never seen the magnets go bad but it does happen...

Re: Rebuilt Magneto '78 Peugeot 103 - No Spark

cool. flywheel looks right. in that video, the guy takes the points out of the equation, and is just using the battery as "points." i don't think that wire in the back is doing any harm. but you could find different spot to ground it - outside the ignition is fine, case bolt etc.

for due diligence you could test the isolated points operation in situ. remove the leads for the condenser and ignition coil and get them out of the way so you can put your flywheel on. then you can test points operation by testing continuity between ground and the hot side of the points - where you had the two wires connected.

if you were to leave the wires connected, you wont be able to pick up on the reading well, if at all, because the condenser and ignition coils are ultimately connected to ground. you need a buzzbox or timing light set up to do it with everything connected.

i have seen either low quality or just wrong points that don't leave enough room and hit stuff they aren't supposed to. cleaner the better too.

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